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{{Short description|Communications and observation tower in Toronto, Canada}}
{{Infobox Skyscraper|
{{About|the Toronto tower|the Alberta building|CN Tower (Edmonton)|the Drake song|CN Tower (song)}}
building_name = CN Tower|
{{Pp-vandalism|small=yes}}
image = [[Image:Toronto's CN Tower.jpg|240px|center|Toronto's CN Tower.]] [[Toronto]]'s CN Tower. |
{{Pp-move|small=yes}}
built = 1973–1976|
{{Use mdy dates|date=October 2013}}
use = mixed use|
{{Use Canadian English|date=April 2021}}
___location = [[Toronto]], [[Canada]]|
{{Infobox building
roof = 457.2 m (1,500 ft)|
| top_floorname = 446.5CN m (1,465 ft)|Tower
| antenna_spire native_name = 553.3''Tour m (1,815 ft)|CN''
| alternate_names = Canadian National Tower, Canada's National Tower
floor_count = 181 (equivalent)|
| floor_area status = ?|Complete
| image = Toronto - ON - Toronto Harbourfront7.jpg
elevator_count = 6|
| caption = The CN Tower as seen from the [[Billy Bishop Toronto City Airport|Toronto City Centre Airport]] in September 2008, it is currently the [[List of tallest freestanding structures|world's 10th<!--See linked article--> tallest free-standing structure on land]]<ref name=tallest>{{cite web| url=http://www.skyscrapercenter.com/x/2897013| title=Compare Data: Results| publisher=[[Council on Tall Buildings and Urban Habitat|The Skyscraper Center]]}}</ref><ref>{{cite web| url=https://www.thestar.com/news/gta/article/698968| title=CN Tower retains world record as tallest 'tower'| date=September 22, 2009| work=[[Toronto Star]]| access-date=August 25, 2017| archive-date=October 22, 2012| archive-url=https://web.archive.org/web/20121022133106/http://www.thestar.com/news/gta/article/698968| url-status=dead}}</ref>
architect = WZMH Architects|
| address = {{nowrap|290 Bremner Boulevard}}<br />[[Toronto]], [[Ontario]]<br />M5V 3L9
skyscraperpage_id = 21|
| coordinates = {{Coord|43|38|33.2|N|79|23|13.5|W|region:CA-ON_type:landmark|display=inline,title}}
emporis_id = 112537|
| start_date = {{start date and age|1973|2|6|df=y}}<ref name="skyscraper"/><ref name="emporis"/>
| topped_out_date = {{start date and age|1975|4|2|df=y}}
| completion_date = 1976
| architect = [[WZMH Architects]]: <br /> [[John Andrews (architect)|John Andrews]], Webb Zerafa, Menkes Housden<ref name="great"/>
| owner = [[Canada Lands Company]]
| cost = {{CAD|63,000,000|link=yes}}<ref name="emporis"/>
| top_floor = {{convert|446.5|m|ft|1|abbr=on}}
| floor_count = 8 (7 in the main pod, 1 in the sky pod)
| references = <ref name="skyscraper">{{skyscraperpage|21}}</ref><ref name="emporis">{{Cite web |url=https://www.emporis.com/buildings/112537 |archive-url=https://web.archive.org/web/20150923224613/https://www.emporis.com/buildings/112537 |url-status=usurped |archive-date=September 23, 2015 |title=Emporis building ID 112537 |work=[[Emporis]]}}</ref><ref name="great"/>
| highest_prev = [[Ostankino Tower]]
| highest_start = 1975<ref name="records"/>
| highest_end = 2007<ref>{{cite news|url=https://www.thestar.com/news/gta/article/256177--cn-tower-no-longer-world-s-tallest|archive-url=https://archive.today/20130204035414/http://www.thestar.com/news/gta/article/256177--cn-tower-no-longer-world-s-tallest| url-status=dead|archive-date=February 4, 2013|work=Toronto Star|title=CN Tower no longer world's tallest|date=September 13, 2007}}</ref>
| highest_next = [[Burj Khalifa]]
| building_type = Mixed use:<br /> Observation, telecommunications, attraction, restaurant
| architectural = {{cvt|553.3|m}}
| antenna_spire = {{cvt|96.1|m}}
| roof = {{cvt|457.2|m}}
| elevator_count = 9<ref name="great"/>
| main_contractor = [[Foundation Company of Canada]]
| public_transit = [[Union Station (Toronto)|Union Station]]<br />[[St. Andrew station]]
| opening = {{start date and age|1976|6|26|df=y}}
| website = {{URL|https://www.cntower.ca/}}
| mapframe-marker = communications-tower
}}
The '''CN Tower''', at [[1 E2 m|553.33]] [[metre]]s (1,815 feet, 5 inches) tall, is the [[world's tallest freestanding structure on land]]. It is located in the [[city]] of [[Toronto]], [[Ontario]], [[Canada]], and is considered the signature icon of the city; more than two million international visitors are attracted annually to the tower<ref name="FACTS">
{{cite paper
|title=Facts at a Glance
|url=http://www.cntower.ca/portal/Secure/Community/417/Documents/PressKit2005/2005%20Facts%20at%20a%20Glance.pdf
|format=[[PDF]]
|publisher=CN Tower
|date=[[2005]]
}}</ref>.
[[Guinness World Records]] has listed the CN Tower as the world's tallest "building" for 30 years<ref name="GWR">{{cite web
|url=http://www.guinnessworldrecords.com/content_pages/record.asp?recordid=49675
|title=Tallest Building
|work=Science and Technology: Buildings
|publisher=Guinness World Records
}}</ref>.
 
The '''CN Tower''' originally({{langx|fr|Tour referredCN}}) tois a {{convert|553.3|m|ft|1|abbr=on|adj=mid|-high}} communications and observation [[tower]] in [[Toronto]], Ontario, Canada.<ref name="skyscraper"/><ref name="CNTower">{{cite web| url=http://www.cntower.ca/portal/GetPage.aspx?at=848| title=Canada's Wonder of the World| publisher=CN Tower| access-date=September 26, 2007| archive-url=https://web.archive.org/web/20070723015815/http://www.cntower.ca/portal/GetPage.aspx?at=848| archive-date=July 23, 2007}}</ref> Completed in 1976, it is located in [[downtown Toronto]], built on the former [[Railway Lands]]. Its name "CN" referred to [[Canadian National Railway|Canadian National]], butthe railway company that followingbuilt the tower. Following the railway's decision to [[Divestment|divest]] non-core freight railway assets, prior to the company's [[privatization]] in [[1995]], theit CNtransferred Towerthe was transferredtower to the [[Canada Lands Company]] (CLC), a federal [[Crown corporation]] responsible for [[real estate]] development. Since the citizens of Toronto wished to retain the name ''CN Tower'', the abbreviation ''CN'' now officially stands for ''Canadagovernment's National''real ratherestate than the original ''Canadian National''portfolio.
 
The CN Tower held the record for the [[List of tallest freestanding structures|world's tallest free-standing structure]] for 32 years, from 1975 until 2007, when it was surpassed by the [[Burj Khalifa]], and was the [[List of tallest towers|world's tallest tower]] until 2009 when it was surpassed by the [[Canton Tower]].<ref>{{cite news| url=https://www.telegraph.co.uk/travel/galleries/tallest-structures-in-the-world-through-history/structures13/ |archive-url=https://ghostarchive.org/archive/20220111/https://www.telegraph.co.uk/travel/galleries/tallest-structures-in-the-world-through-history/structures13/ |archive-date=January 11, 2022 |url-access=subscription |url-status=live|title=The world's tallest structures through history| date=April 20, 2017| work=[[The Daily Telegraph]]| ___location=[[London]]}}{{cbignore}}</ref><ref>{{cite web| url=http://www.theworldwonders.com/modern-cn-tower.html| title=Modern World Wonders-CN Tower| website=www.theworldwonders.com| access-date=July 31, 2017| archive-date=July 28, 2019| archive-url=https://web.archive.org/web/20190728094343/https://theworldwonders.com/modern-cn-tower.html| url-status=dead}}</ref><ref>{{cite news| url=https://www.reuters.com/article/us-ba-tower-elevator-idUSN0923507720080409| title=CN Tower's glass-floored lift not for faint-hearted| date=April 9, 2008| publisher=[[Reuters]]| last=Mollins| first=Julie}}</ref><ref name="canton">{{cite web| url=https://skyscraperpage.com/cities/?buildingID=36975| title=Canton Tower, Guangzhou| website=[[SkyscraperPage]]}}</ref> It is currently the tenth-tallest free-standing structure in the world and remains the tallest free-standing structure on land in the [[Western Hemisphere]]. In 1995, the CN Tower was declared one of the modern Seven [[Wonders of the World]] by the [[American Society of Civil Engineers]]. It also belongs to the World Federation of Great Towers.<ref name="great">{{cite web| title=Facts and visitor information on the CN Tower in Canada| url=http://www.great-towers.com/towers/cn-tower/| publisher=The World Federation of Great Towers| access-date=January 2, 2013| archive-url=https://web.archive.org/web/20160929223832/http://www.great-towers.com/towers/cn-tower/| archive-date=September 29, 2016| url-status=dead}}</ref><ref>{{cite web| last=Rosenberg| first=Matt| title=Seven Wonders of the World| url=https://www.thoughtco.com/seven-wonders-of-the-world-1435155| publisher=[[People Inc.|ThoughtCo]]| date=March 3, 2017| access-date=August 30, 2017}}</ref><ref name="info">{{cite web| title=The Seven Wonders of the Modern World| url=http://www.infoplease.com/ipa/A0923082.html|publisher=Infoplease.com| access-date=January 2, 2013}}</ref>
==Structure==
[[Image:CNTowerLookingStraightUp.JPG|thumb|240px|left|The CN Tower seen when looking directly up from the ground level.]]
The CN Tower consists of several substructures. The main portion of the Tower consists of a hollow concrete pillar containing the elevators, stairwells and power and plumbing connections. On top is the 102 m (335 ft) metal broadcast antenna, carrying TV and radio signals. There are two main visitor areas, the main seven-story pod located at the 330 m (1,100 ft) level, and the '''SkyPod''' at 447 m (1,465 ft), just below the antenna. Microwave antennas ring the lower portion of the main pod, protected in a large white donut-shaped [[radome]].
 
It is a signature icon of Toronto's [[skyline]]<ref>{{cite journal|last=Plummer|first=Kevin|date=September 4, 2007|title=The CN Tower Is Dead. Long Live the CN Tower!|url=http://torontoist.com/2007/09/the_cn_tower_is.php|access-date=November 17, 2008|journal=The Torontoist|archive-url=https://web.archive.org/web/20100113142042/http://torontoist.com/2007/09/the_cn_tower_is.php|archive-date=January 13, 2010|url-status=dead}}</ref><ref>[http://www.canada.com/topics/travel/story.html?id=057d78dc-4964-422f-ba85-361425ea8126&k=3499 CN Tower celebrates 30th birthday], Broadcast News/canada.com, June 26, 2006 {{webarchive|url=https://web.archive.org/web/20150622034959/http://www.canada.com/topics/travel/story.html?id=057d78dc-4964-422f-ba85-361425ea8126&k=3499|date=June 22, 2015}}</ref> and attracts more than two&nbsp;million international visitors annually.<ref name="great"/><ref name="FACTS">{{cite web|title=World Wonders and Facts at a Glance|url=http://www.cntower.ca/en-ca/about-us/architecture/world-wonders-and-facts-at-a-glance.html|format=PDF|publisher=CN Tower|access-date=August 30, 2017|archive-date=August 31, 2017|archive-url=https://web.archive.org/web/20170831001939/http://www.cntower.ca/en-ca/about-us/architecture/world-wonders-and-facts-at-a-glance.html|url-status=dead}}</ref> It houses several observation decks, a revolving restaurant at some {{convert|1150|ft|sigfig=2|order=flip}}, and an entertainment complex.<ref>{{Cite web|title=CN Tower {{!}} building, Toronto, Ontario, Canada {{!}} Britannica|url=https://www.britannica.com/topic/CN-Tower|access-date=2022-01-27|website=www.britannica.com|language=en}}</ref>
The '''Sky Pod''', situated high above the main observation floor, is the highest public observation deck in the world. From its top, it is possible on a clear day to see approximately 100-120 km (62-74 mi) away and even see an outline of the city of [[Rochester, New York|Rochester]] across [[Lake Ontario]] in the [[United States]], or the mist rising from [[Niagara Falls]].
 
== History ==
At 342 m (1,122 ft) is the [[glass floor|Glass Floor]] and Outdoor Observation Deck. The Glass Floor is 23.8 m² (256 sq ft) and can withstand a pressure of 4,100 kPa (600 lbs/sq in) or 14 large [[hippopotamus]]es. The glass floor consists of thermal glass units that are 64 mm (2½ in) thick, consisting of a pane of 25 mm (1 in) laminated glass, a 25 mm (1 in) airspace and a pane of 13 mm (½ in) laminated glass. Some people experience [[vertigo (medical)|vertigo]] by walking out on the glass floor and looking down at the ground below.
[[File:Toronto - ON - CN Tower bei Nacht2.jpg|thumb|left|upright|CN Tower from the [[Toronto Islands]]]]
 
The original concept of the CN Tower was first conceived in 1968 when the [[Canadian National Railway]] wanted to build a large television and radio communication platform to serve the Toronto area, and to demonstrate the strength of Canadian industry and CN in particular. These plans evolved over the next few years, and the project became official in 1972.
At 346 m (1,136 ft) is the Horizons Cafe and the Lookout Level, and at 351 m (1,150 ft) is the 360 Restaurant, which completes a full revolution once every 72 minutes.
 
The tower would have been part of Metro Centre (see [[CityPlace, Toronto|CityPlace]]), a large development south of [[Front Street (Toronto)|Front Street]] on the [[Railway Lands]], a large railway switching yard that was being made redundant after the opening of the [[MacMillan Yard]] north of the city in 1965 (then known as Toronto Yard). Key project team members were NCK Engineering as structural engineer; [[John Andrews (architect)|John Andrews Architects]]; Webb, Zerafa, Menkes, Housden Architects; Foundation Building Construction; and Canron (Eastern Structural Division).<ref name="skyscraper" /><ref name="emporis" /><ref name="CNTower" />
The structure's microwave receivers for distant signals are housed at 338 m (1,109 ft), and the top of the transmission antenna is at the apex of the tower.
 
As Toronto grew rapidly during the late 1960s and early 1970s, multiple skyscrapers were constructed in the downtown core, most notably [[First Canadian Place]], which has [[Bank of Montreal]]'s head offices. The reflective nature of the new buildings reduced the quality of broadcast signals, requiring new, higher antennas that were at least {{convert|300|m|ft|abbr=on}} tall. The radio wire is estimated to be {{convert|102|m|ft}} long in 44 pieces, the heaviest of which weighs around {{convert|8|t|ST LT}}.<ref>{{Cite news |last=Sienkiewicz |first=Alexandra |date=Aug 16, 2017 |title=Here's what the CN Tower was intended for, before the glass floor and EdgeWalk |publisher=CBC |url=https://www.cbc.ca/news/canada/toronto/cn-tower-beginnings-1.4249393}}</ref>
A metal staircase with 1,776 steps reaches the Lookout level, reaching 2,579 steps by the SkyPod, and is the tallest metal staircase on earth. These stairs are intended for emergency use and are not open to the public, except for twice per year for charity stair-climb events: around [[Earth Day]] in the spring by the [[World Wildlife Fund]] and in the fall by the [[United Way]]'s Toronto chapter. The average climber takes approximately 30 minutes to climb to the base of the radome (the white ring around the bottom of the main pod), but the fastest climb on record is 7 minutes and 52 seconds in 1989 by Brendan Keenoy, an Ontario Provincial Police Officer. The fastest record for a woman belongs to Chrissy Redden, who climbed the stairs in 2000 in 11 minutes and 52 seconds. In 2002, Canadian Olympian & Paralympic Champion Jeff Adams climbed the stairs of the CN Tower in a specially designed wheelchair.
 
At the time, most data communications took place over [[Microwave#Communication|point-to-point microwave]] links, whose dish antennas covered the roofs of large buildings. As each new skyscraper was added to the downtown, former line-of-sight links were no longer possible. CN intended to rent "hub" space for microwave links, visible from almost any building in the Toronto area.
==History==
[[Image:Cntower_unfinished.jpg|thumb|240px|right|The CN Tower under construction in 1974. The slipform is at its ultimate height. The CN roundhouse can be seen in the lower right, the Toronto Dominion Centre in the upper left.]]
The concept of the CN Tower originated from a 1968 [[Canadian National Railway]] desire to build a large TV and radio communication platform to serve the Greater Toronto Area, as well as demonstrating the strength of Canadian industry, and CN in particular. These plans evolved over the next few years, until the project became "official" in 1972. The Tower would have been part of '''Metro Center''' (see [[Cityplace (Toronto)|Cityplace]]), a large development south of Front Street on the Railway Lands, a large railway switching yard that was being made redundant by newer yards outside the city. Key project team members were NCK Engineering as structural engineer; John Andrews Architects; Webb, Zerafa, Menkes, Housden Architects; Foundation Building Construction and Canron (Eastern Structural Division).
 
The original plan for the tower envisioned a tripod consisting of three independent cylindrical "pillars" linked at various heights by structural bridges. Had it been built, this design would have been considerably shorter, with the metal antenna located roughly where the concrete section between the main level and The Top lies today. As the design effort continued, it evolved into the current design with a single continuous hexagonal core to The Top, with three support legs blended into the hexagon below the main level, forming a large Y-shape structure at the ground level.<ref name="CNTower"/><ref name="ieee">{{cite web| author=[[The Hahn Company|TrizecHahn]]| title=A Brief Overview of the CN Tower| url=http://www.ieee.ca/millennium/cntower/cntower_overview.html| publisher=[[Institute of Electrical and Electronics Engineers]]| access-date=January 2, 2013| archive-date=March 3, 2016| archive-url=https://web.archive.org/web/20160303220107/http://www.ieee.ca/millennium/cntower/cntower_overview.html| url-status=dead}}</ref>
At the time, Toronto was a "boom town" and the late 1960s and early 1970s had seen the construction of numerous large [[skyscraper]]s in the downtown core. This made broadcasting into the downtown area very difficult due to reflections off the buildings. The only solution would be to raise the antennas above the buildings, demanding a tower over 1,000 ft (305 m) tall. Additionally, at that time most data communications took place over point-to-point [[microwave]] links, whose dish antennas used to cover the roofs of large buildings. As each new skyscraper was added to the downtown, former line-of-sight links were no longer possible. CN intended to rent "hub" space for microwave links, visible from almost any building in the Toronto area.
 
The idea for the main level in its current form evolved around this time, but the Space Deck (currently named The Top, and originally dubbed 'Bud's Bubble' named after Bud Andrews) was not part of the plans until later. Bud Andrews (President of the Metro Centre Developments Group) felt that visitors would feel the higher observation deck would be worth paying extra for, and the costs in terms of construction were not prohibitive. Also around this time, it was realized that the tower could become the world's tallest free-standing structure to improve signal quality and attract tourists, and plans were changed to incorporate subtle modifications throughout the structure to this end.<ref name="CNTower"/><ref name="ieee"/>
The original plan for the tower consisted of three independent "pillars" linked at various heights by structural bridges. This design would be considerably shorter than the Tower as it is today, the TV antenna located roughly where the concrete section between the SkyPod and Space Deck lies today. As the design effort continued, it evolved into the current design with a single continuous hexagonal core to the 447 m (1,465 ft) Space Deck level, with three support legs blended into the hexagon below the SkyPod level at 335 m (1,100 ft), forming a large Y-shape structure at the ground level.
 
=== Construction ===
The idea for the SkyPod in its current form evolved around this time, but the Space Deck was not part of the plans until some time later. One engineer in particular felt that visitors would feel the higher observation deck would be worth paying extra for, and the costs in terms of construction were not prohibitive. It was also some time around this point that it was realized that the Tower could become the world's tallest structure, and plans were changed to incorporate subtle changes throughout the tower to this end.
[[File:Ripleys Aquarium Toronto map.png|thumb|Map of the area immediately surrounding CN Tower shortly before the opening of [[Ripley's Aquarium of Canada]] in 2013]]
 
The CN Tower was built by [[Foundation Company of Canada]] with Canron of Etobicoke handling the steel and antenna fabrication work.
Construction on the CN Tower started on [[February 6]], [[1973]] with massive excavations at the tower base for the foundation. By the time the foundation was complete, 56,234 metric tonnes (62,000 tons) of dirt and shale were removed to a depth of 15 m (50 ft) in the center, and a base incorporating 7,034 m³ (9,200 cu yd) of concrete with 454 metric tonnes (500 tons) of steel re-bar and 36 metric tonnes (40 tons) of steel cable had been built to a thickness of 6.7 m (22 ft). This portion of the construction was fairly rapid, with only four months needed between the start and the foundation being ready for construction on top.
 
Construction began on February 6, 1973, with massive excavations at the tower base for the foundation. By the time the foundation was complete, {{convert|56000|t|ST LT|abbr=on|lk=on}} of [[soil|earth]] and [[shale]] were removed to a depth of {{convert|15|m|ft|1|abbr=on}} in the centre, and a base incorporating {{convert|7000|m3|cuyd|abbr=on}} of concrete with {{convert|450|t|ST LT|0|abbr=on}} of [[rebar]] and {{convert|36|t|ST LT|abbr=on}} of [[wire rope|steel cable]] had been built to a thickness of {{convert|6.7|m|ft|abbr=on}}. This portion of the construction was fairly rapid, with only four months needed between the start and the foundation being ready for construction on top.<ref name="ieee"/>
To build the main support pillar, a hydraulically-raised [[slipform]] was built at the base. This was a fairly impressive engineering feat on its own, consisting of a large metal platform that raised itself on jacks at about 6 m (20 ft) per day as the concrete below dried out. Concrete was poured continuously by a team of 1,537 people until February 22, 1974, during which it had already become the tallest structure in Canada, surpassing the recently built [[Superstack]] which was built using similar methods. In total, the tower contains 40 524 m³ (53,000 cu yd) of concrete, all of which was mixed on-site in order to ensure batch consistency. Through the pour, the vertical accuracy of the tower was maintained by comparing the slip form's ___location to massive [[plumbob]]s hanging from it, observed by small telescopes from the ground. Over the height of the tower, it varies from true by only 2.9 cm (1.1 in).
 
To create the main support pillar, workers constructed a hydraulically raised [[Slip forming|slipform]] at the base. This was a fairly unprecedented engineering feat on its own, consisting of a large metal platform that raised itself on jacks at about {{convert|6|m|ft|abbr=on}} per day as the concrete below set. Concrete was poured Monday to Friday (not continuously) by a small team of people until February 22, 1974, at which time it had already become the tallest structure in Canada, surpassing the recently built {{convert|381|m|ft|adj=on}} tall [[Inco Superstack]] in [[Greater Sudbury|Sudbury]], built using similar methods.
In August, construction of the SkyPod commenced. Using 45 hydraulic jacks attached to cables strung from a temporary steel crown anchored to the top of the tower, twelve giant steel and wooden bracket forms were slowly raised, ultimately taking about a week to crawl up to their final position. These forms were not only used to create the brackets which support the SkyPod, but also as a base for the construction of the SkyPod itself.
 
The tower contains {{convert|40500|m3|cuyd|abbr=on}} of concrete, all of which was mixed on-site in order to ensure batch consistency. Through the pour, the vertical accuracy of the tower was maintained by comparing the slip form's ___location to massive [[plumb bob]]s hanging from it, observed by small telescopes from the ground. Over the height of the tower, it varies from true vertical accuracy by only {{convert|29|mm|in|1|abbr=on}}.<ref name="CNTower" /><ref name="ieee" />
The Space Deck was built of concrete poured into a wooden frame attached to rebars at the lower level Deck, and then re-enforced with a large steel compression band around the outside.
 
[[File:CN Tower40 construction skycrane March 1975 01c.jpg|thumb|right|upright|Skycrane "Olga" lifting antenna segment]]
The antenna was originally to be raised by crane as well, but during construction the [[Sikorsky Skycrane]] helicopter became available when the [[US Army]] sold off their examples to civilian operators. The helicopter was first used to remove the crane, and then flew the antenna up in 36 sections. Flights were a minor tourist attraction of their own, and the schedule was printed in the local newspapers. Use of the helicopter saved months of construction time, with this phase taking only 3 and a half weeks instead of the planned six months. The tower was topped off on April 2, 1975 after 40 months of construction, officially capturing the height record from [[Moscow]]'s [[Ostankino Tower]], and bringing the total weight to 117,910 metric tonnes (130,000 tons).
 
In August 1974, construction of the main level commenced. Using 45 hydraulic jacks attached to cables strung from a temporary steel crown anchored to the top of the tower, twelve giant steel and wooden bracket forms were slowly raised, ultimately taking about a week to crawl up to their final position. These forms were used to create the brackets that support the main level, as well as a base for the construction of the main level itself. The Top was built of concrete poured into a wooden frame attached to rebar at the lower level deck, and then reinforced with a large steel compression band around the outside.<ref name="ieee"/>
Two years into the construction, plans for Metro Centre were scrapped, leaving the Tower isolated on the Railway Lands in what was then largely abandoned light-industrial space. This caused serious problems with access to the tower. Ned Baldwin, project architect with John Andrews, wrote at the time that "All of the logic which dictated the design of the lower accommodation has been upset," and that "Under such ludicrous circumstances Canadian National would hardly have chosen this ___location to build."
 
While still under construction, the CN Tower officially became the world's tallest free-standing structure on March 31, 1975.<ref name=records/>
The CN Tower opened to the public on [[June 26]], [[1976]], although the official opening date was October 1st. The construction costs of approximately $330 million 2005 Canadian Dollars (approximately $260 million 2005 US Dollars) were repaid in fifteen years. CN sold the Tower prior to taking the company public in 1995, when they decided to divest themselves of all operations not directly related to their core freight shipping businesses.
 
The antenna was originally to be raised by crane as well, but, during construction, the [[Sikorsky S-64 Skycrane]] helicopter became available when the [[United States Army]] sold one to civilian operators. The helicopter, named "Olga", was first used to remove the crane, and then flew the antenna up in 36 sections.
As the area around the Tower was developed, particularly with the introduction of the [[Metro Toronto Convention Centre]] and [[Skydome]] (known as the Rogers Centre since 2005), the former railway "wasteland" disappeared and the Tower became the centre of a newly developing entertainment area. Access was greatly improved with the construction of the '''SkyWalk''' in 1989, which connected the Tower and SkyDome to the nearby [[Union Station (Toronto)|Union Station]] railway and subway station. By the mid-1990s it was the center of a thriving tourist district. The entire area continues to be an area of intense building, notably a recent boom in [[condominium]] construction. Although the area did not develop as CN and CP initially planned, along an east-west axis, in the end the Tower terminated a long view south down John Street from Toronto's "entertainment district".
 
The flights of the antenna pieces were a minor tourist attraction of their own, and the schedule was printed in local newspapers. Use of the helicopter saved months of construction time, with this phase taking only three and a half weeks instead of the planned six months. The tower was topped-off on April 2, 1975, after 26 months of construction, officially capturing the height record from [[Moscow]]'s [[Ostankino Tower]], and bringing the total mass to {{convert|118000|t|ST LT|abbr=on}}.
From 1997 to January 2004, [[TrizecHahn Corporation]] managed the building and instituted several expansion projects including a $26 million entertainment expansion and revitalization that included the addition of two new elevators (to a total of six) and the relocation of the staircase from the north side leg to inside the core of the building, a conversion that also added nine stairs to the climb.
 
Two years into the construction, plans for Metro Centre were scrapped, leaving the tower isolated on the Railway Lands in what was then a largely abandoned light-industrial space. This caused serious problems for tourists to access the tower. Ned Baldwin, project architect with John Andrews, wrote at the time that "All of the logic which dictated the design of the lower accommodation has been upset," and that "Under such ludicrous circumstances Canadian National would hardly have chosen this ___location to build."<ref>{{cite book| last=Fulford| first=Robert| date=March 13, 1996| title=Accidental city: the transformation of Toronto| publisher=MacFarlane, Walter & Ross| page=32| isbn=978-0395773079}}</ref>
== Size Comparisons ==
{{details|World's tallest structures|analysis of the tallest man-made structures}}
In 1995, the CN Tower was declared one of the modern [[Seven Wonders of the World#Modern Wonders|Seven Wonders of the World]] by the [[American Society of Civil Engineers]]. It also belongs to the [[World Federation of Great Towers]]. The following year, the [[Guinness Book of World Records]] officially changed the CN Tower's classification to "World's Tallest Building and Free-Standing Structure". Today, the Guinness World Records state the CN Tower as the "Tallest Freestanding Tower". This is because the [[Petronius Platform]] oil rig in the [[Gulf of Mexico]] is taller, yet most of the rig is underwater.
 
==== Phases of construction ====
There are also many guyed towers taller than the CN Tower, the current tallest being the [[KVLY-TV mast|KVLY-TV tower]] in [[North Dakota]] at 628 m (2,063 ft) tall (see [[List of masts]]), but these are [[guy-wire]] supported structures and not classified as free-standing. The [[Petronius Compliant Tower]] (an [[oil platform]]) at 645 m (2,116 ft), is a taller free-standing structure, however all but its top is underwater.
<gallery mode="packed" heights="135px" style="text-align:left">
File:CN Tower footings 1973.jpg|Constructing the base, July 1973
File:Cntower1974.jpg|Brackets being raised, August 1974
File:CN Tower50 construction skycrane March 1975 01d.jpg|Helicopter lifting part of antenna, March 1975
File:CN Tower under construction (April 1975)-Edit(Taxi).jpg|Main pod construction, April 1975
File:CN Tower under construction.jpg|Nearing completion, December 1975
File:CN Tower 1976.jpg|Two months after opening, August 1976
</gallery>
 
=== Opening ===
There are currently five proposals for towers whose final heights are to exceed the CN tower's<ref name="Emporis">
The CN Tower opened on June 26, 1976.<ref>{{cite news| title=CN Tower celebrates 40 years as a tourist magnet and lightning rod| date=June 25, 2016| access-date=June 27, 2016| url=https://www.thestar.com/news/gta/2016/06/25/cn-tower-celebrates-40-years-as-a-tourist-magnet-and-lightning-rod.html| last=Botelho-Urbanski| first=Jessica| work=Toronto Star}}</ref> The construction costs of approximately {{CAD|63 million|link=yes}} (${{formatprice|{{Inflation|CA|63000000|1976}}}} in {{Inflation-year|CA}} dollars){{inflation-fn|CA}} were repaid in fifteen years.<ref>{{Cite web|title=Building the CN Tower|url=https://dozr.com/blog/building-the-cn-tower|access-date=2021-09-08|website=DOZR|language=en}}</ref>
{{cite news
|url=http://www.emporis.com/en/bu/nc/ne/?id=101602
|first=Edward
|last=Chamberlain
|title=CN Tower Marks 30 Years At The Top
|publisher=[[Emporis|Emporis Buildings]]
|date=[[2006-06-26]]
}}</ref>, three of which are currently under construction. At the forefront, the [[Burj Dubai]] would, according to present claims by its developers, become a taller free-standing land structure than CN Tower sometime in 2008; work on that tower has, [[as of 2006|as of July 2006]], reached the 60th floor and 210 metres (690 ft)<!-- According to [[Burj Dubai]]-->.
 
From the mid-1970s to the mid-1980s, the CN Tower was practically the only development along Front Street West; it was still possible to see Lake Ontario from the foot of the CN Tower due to the expansive parking lots and lack of development in the area at the time. As the area around the tower was developed, particularly with the completion of the [[Metro Toronto Convention Centre]] (north building) in 1984 and SkyDome in 1989 (renamed [[Rogers Centre]] in 2005), the former Railway Lands were redeveloped and the tower became the centre of a newly developing entertainment area. Access was greatly improved with the construction of the [[SkyWalk]] in 1989, which connected the tower and SkyDome to the nearby [[Union Station (Toronto)|Union Station]] railway and [[Union station (TTC)|subway station]], and, in turn, to the city's [[Path (Toronto)|Path]] underground pedestrian system. By the mid-1990s, it was the centre of a thriving tourist district. The entire area continues to be an area of intense building, notably a [[Manhattanization|boom]] in [[condominium]] construction in [[Canadian property bubble|the early 21st century]], as well as the 2013 opening of the [[Ripley's Aquarium of Canada|Ripley's Aquarium]] by the base of the tower.<ref name="great"/><ref name="CNTower"/><ref name="ieee"/>
[[Image:VIEW_FROM_CN_TOWER..JPG|thumb|250px|Left|View from the tower's Glass Floor.]]
 
===Early years ===
The builders of the CN Tower did not expect that it would hold the tallest structure record for thirty years. Previous record holders had quickly been supplanted. Several rivals have been proposed and most schemes collapsed. This is partly due to the development of cable television soon after the tower was built which greatly reduced the need for such broadcasting centres, especially in urban areas. Only in cities are there enough tourists to make such a tower viable as a tourist attraction.
When the CN Tower opened in 1976, there were three public observation points: The Top (then known as the Space Deck) that stands at {{convert|447|m|ft|abbr=on}}, the Indoor Observation Level (later named Main Observation Level) at {{convert|346|m|ft|abbr=on}}, and the Outdoor Observation Terrace (at the same level as the Glass Floor) at {{convert|342|m|ft|abbr=on}}.<ref name="great"/><ref name="ieee"/> One floor above the Indoor Observation Level was the Top of Toronto Restaurant (now named "360 The Restaurant at the CN Tower"), which completed a revolution once every 72 minutes.<ref>{{cite web |title=General Information |url=https://www.cntower.ca/site_Files/Content/PDF/Press_Kit/CN_Tower_General_Information_2013_Revised.pdf |publisher=CN Tower |date=2013 |access-date=August 4, 2018 |archive-date=December 1, 2020 |archive-url=https://web.archive.org/web/20201201061602/https://www.cntower.ca/site_Files/Content/PDF/Press_Kit/CN_Tower_General_Information_2013_Revised.pdf |url-status=dead }}</ref>
 
The tower would garner worldwide media attention when stuntman [[Dar Robinson]] jumped off the CN Tower on two occasions in 1979 and 1980. The first was for a scene from the movie ''[[Highpoint (film)|Highpoint]]'', in which Robinson received {{CAD|250,000}} (${{Inflation|CA|250000|1979|fmt=c}} in {{Inflation-year|CA}} dollars){{inflation-fn|CA}} for the stunt. The second was for a personal [[Documentary film|documentary]]. The first stunt had him use a parachute which he deployed three seconds before impact with the ground, while the second one used a wire decelerator attached to his back.<ref name="robinson">{{cite news| title=Man Jumps From CN Tower With No Parachute (Thirty Years Ago)| url=http://torontoist.com/2010/02/man_jumps_from_cn_tower_with_no_parachute_thirty_years_ago/| first=Steve| last=Kupferman| date=February 26, 2010| work=Torontoist| access-date=November 10, 2013| archive-date=November 10, 2013| archive-url=https://web.archive.org/web/20131110154900/http://torontoist.com/2010/02/man_jumps_from_cn_tower_with_no_parachute_thirty_years_ago/| url-status=dead}}</ref>
==Usage==
The CN Tower has been and continues to be used as a communications tower for a number of different media, and by numerous companies:
===Television broadcasters===
* [[CBC]]
* [[CFTO-TV]]
* [[CITY-TV|Citytv Toronto]]
* [[CIII-TV|Global Ontario]]
* [[LOOK TV]] (a digital cable provider)
* [[Rogers Cable]]
* [[CKXT-TV|Sun TV]]
 
On June 26, 1986, the tenth anniversary of the tower's opening, [[High-rise building|high-rise]] firefighting and rescue advocate [[Dan Goodwin]], in a sponsored publicity event, used his hands and feet to climb the outside of the tower, a feat he performed twice on the same day. Following both ascents, he used multiple rappels to descend to the ground.<ref>{{cite web| last=Goodwin| first=Dan| title=Dan Goodwin's Building Climbs| url=http://www.skyscraperdefense.com/building_climbs.html| publisher=Skyscraperdefense.com| access-date=January 2, 2013}}</ref>
===AM/FM radio===
 
{| class="wikitable" width="100%" align="center" style="text-align: center"
From 1985 to 1992, the CN Tower basement level hosted the world's first flight [[simulator ride]], [[Tour of the Universe]], based on the flight of a [[Space Shuttle]]. The ride was replaced in 1992 with a similar attraction entitled "Space Race." It was later dismantled and replaced by two other rides in 1998 and 1999.
 
=== The 1990s and 2000s ===
A glass floor at an elevation of {{convert|342|m|ft|abbr=on}} was installed in 1994.<ref name="ieee"/> Canadian National Railway sold the tower to Canada Lands Company prior to privatizing the company in 1995, when it divested all operations not directly related to its core freight shipping businesses. The tower's name and wordmark were adjusted to remove the CN railways logo, and the tower's official name was renamed Canada's National Tower (from Canadian National Tower),<ref name="CN Tower Name">{{cite web|url=http://www.cntower.ca/portal/GetPage.aspx?at=848#The%20Tower|title="Canada's Wonder of the World"|work=CN Tower: Plan Your Visit > Who We Are|publisher=CN Tower - Canada Lands Company|access-date=February 8, 2007|archive-date=July 23, 2007|archive-url=https://web.archive.org/web/20070723015815/http://www.cntower.ca/portal/GetPage.aspx?at=848#The%20Tower|url-status=dead}}</ref> though the tower is commonly called the CN Tower.
 
Further changes were made from 1997 to January 2004: [[The Hahn Company|TrizecHahn Corporation]] managed the tower and instituted several expansion projects including a {{CAD|26 million}} entertainment expansion, the 1997 addition of two new elevators (to a total of six) and the consequential relocation of the staircase from the north side leg to inside the core of the building, a conversion that also added nine stairs to the climb. TrizecHahn also owned the [[Willis Tower]] (Sears Tower at the time) in Chicago approximately at the same time.
 
In 2007, [[light-emitting diode]] (LED) lights replaced the incandescent lights that lit the CN Tower at night. This was done to take advantage of the cost savings of LED lights over incandescent lights. The colour of the LED lights can change, compared to the constant white colour of the incandescent lights. On September 12, 2007, [[Burj Khalifa]] in Dubai, then under construction and known as Burj Dubai, surpassed the CN Tower as the world's tallest free-standing structure on land.<ref name="CBCSurpassed">{{cite news| title=CN Tower dethroned by Dubai building |url= https://www.cbc.ca/news/canada/cn-tower-dethroned-by-dubai-building-1.639333 |work=[[CBC News]] |date=September 12, 2007 |access-date=April 9, 2008 |archive-url= https://web.archive.org/web/20100619095709/http://www.cbc.ca/canada/story/2007/09/12/cntower-surpassed.html |archive-date=June 19, 2010 |url-status=live |df=mdy }}</ref> In 2008, glass panels were installed in one of the CN Tower elevators, which established a world record ({{convert|346|m|ft|abbr=on}}) for highest glass floor panelled elevator in the world.
 
=== 2010s: EdgeWalk ===
[[File:EdgeWalk on the CN Tower.jpg|thumb|right|EdgeWalk atop the main pod]]
 
On August 1, 2011, the CN Tower opened the EdgeWalk, an amusement in which thrill-seekers can walk on and around the roof of the main pod of the tower at {{convert|356|m|ft|1|abbr=on}}, which is directly above the 360 Restaurant.<ref>{{cite news| title=New CN Tower attraction offers a walk on the outside| url=https://www.thestar.com/news/article/988150--new-cn-tower-attraction-offers-a-walk-on-the-outside| work=Toronto Star| access-date=January 3, 2013| date=May 9, 2011}}</ref> It is the world's highest full-circle, hands-free walk. Visitors are tethered to an overhead rail system and walk around the edge of the CN Tower's main pod above the 360 Restaurant on a {{convert|1.5|m|ft|adj=on}} metal floor.<ref>{{cite web| url=http://www.cntower.ca/en-CA/Plan-Your-Visit/Attractions/EdgeWalk/EdgeWalk-Overview.html| title=Toronto's Most Extreme Attraction| access-date=February 25, 2012| quote=It is the world's highest full circle hands-free walk on a 5 ft (1.5 metres) wide ledge encircling the top of the tower's main pod, 356m/1168ft (116 storeys) above the ground.| publisher=CN Tower| archive-date=March 9, 2012| archive-url=https://web.archive.org/web/20120309075800/http://www.cntower.ca/en-CA/Plan-Your-Visit/Attractions/EdgeWalk/EdgeWalk-Overview.html| url-status=dead}}</ref> The attraction is closed throughout the winter and during periods of electrical storms and high winds.
 
One of the notable guests who visited EdgeWalk was Canadian comedian [[Rick Mercer]], featured as the first episode of the ninth season of his [[CBC Television]] [[news satire]] show, ''[[Rick Mercer Report]]''. There, he was accompanied by Canadian pop singer [[Jann Arden]]. The episode first aired on April 10, 2013.<ref>{{cite web|url=http://www.cbc.ca/mercerreport/episodes/season-9/season-9-episode-1|title=Season 9 - Episode 1|series=Rick Mercer Report|date=April 10, 2013|work=CBC Television}}</ref>{{Non-primary source needed|date=June 2025}}
 
==== 2015 Pan Am Games ====
The tower and surrounding areas were prominent in the [[2015 Pan American Games]] production. In [[2015 Pan American Games opening ceremony|the opening ceremony]], a pre-recorded segment featured track-and-field athlete [[Bruny Surin]] passing the flame to sprinter [[Donovan Bailey]] on the EdgeWalk and parachuting into Rogers Centre. A fireworks display off the tower concluded both the opening and closing ceremonies.
 
==== Canada 150 ====
On July 1, 2017, as part of the nationwide celebrations for [[150th anniversary of Canada|Canada 150]], which celebrated the 150th anniversary of [[Canadian Confederation]], fireworks were once again shot from the tower in a five-minute display coordinated with the tower lights and music broadcast on a local radio station.
 
=== 2020s ===
The CN Tower closed during much of the [[COVID-19 pandemic]]. During much of the pandemic, the gift shop was renovated to take advantage of the lack of visitors from the tower's closure.
 
== Closures ==
*The CN Tower was closed on September 11, 2001, following the [[September 11 attacks|terrorist attacks]] on the [[World Trade Center (1973–2001)|World Trade Center]] in New York City.{{cn|date=November 2024}}
*The CN Tower was closed during the [[2010 G20 Toronto summit|G20 summit]] on June 26–27, 2010, for security reasons, given its proximity to the Metro Toronto Convention Centre and ongoing [[2010 G20 Toronto summit protests|citywide protests and riots]].
*The CN Tower was closed from 2020 to 2021 due to [[COVID-19 pandemic in Toronto|COVID-19 pandemic]] restrictions throughout Ontario.
*The CN Tower was closed on December 16, 2021, due to glass falling off from heavy winds.<ref>{{cite web |url=https://www.cbc.ca/news/canada/toronto/cn-tower-falling-glass-1.6288290 |accessdate=31 December 2021 |title=Glass falls from CN Tower as heavy winds hit Toronto |website=CBC | date=December 16, 2021 }}</ref>
 
== Structure ==
[[File:Subindotorrecn.ogv|thumb|Elevator going up]]
[[File:Restaurante panoramico na Torre CN.ogv|thumb|View from 360 Restaurant]]
[[File:CN Tower SkyPod 2023d.jpg|thumb|View straight down from the SkyPod to the roof of the Observation Level]]
The CN Tower consists of several substructures. The main portion of the tower is a hollow concrete hexagonal pillar containing the [[Stairs|stairwells]] and power and plumbing connections. The tower's six [[elevator]]s are located in the three inverted angles created by the Tower's hexagonal shape (two elevators per angle). Each of the three elevator shafts is lined with glass, allowing for views of the city as the glass-windowed elevators make their way through the tower. The stairwell was originally located in one of these angles (the one facing north), but was moved into the central hollow of the tower; the tower's new fifth and sixth elevators were placed in the hexagonal angle that once contained the stairwell. On top of the main concrete portion of the tower is a {{convert|102|m|ft|1|abbr=on|adj=on}} tall metal broadcast antenna, carrying television and radio signals. There are three visitor areas:<ref>{{Cite web |date=2021-02-26 |title=Inspiring by day, stellar by night {{!}} CN Tower |url=https://www.cntower.ca/inspiring-by-day-stellar-by-night |access-date=2025-05-04 |website=www.cntower.ca |language=en}}</ref>
 
* the Lower Observation Level, located at an elevation of {{convert|342|m|ft|0|abbr=on}}. It contains the Glass Floor and Outdoor Terrace.
* the Main Observation Level, at {{convert|346|m|ft|0|abbr=on}}. It was formerly known as "Indoor Lookout Level" and "Indoor Observation Level".
* The Top, at {{convert|446.5|m|ft|0|abbr=on}}, just below the metal [[Antenna (radio)|antenna]]. It was formerly known as "SkyPod" and "Space Deck".
 
The hexagonal shape is visible between the two highest areas; however, below the main deck, three large supporting legs give the tower the appearance of a large [[tripod]].
 
The main deck level has seven storeys, some of which are open to the public. Below the public areas—at {{convert|338|m|ft|1|abbr=on}}—is a large white donut-shaped [[radome]] containing the structure's [[Ultra high frequency|UHF]] transmitters. The glass floor at the Lower Observation Level has an area of {{convert|24|m2|sqft|0|abbr=on}} and can withstand a pressure of {{convert|4.1|MPa|psi|0|lk=on}}. The floor's thermal glass units are {{convert|64|mm|in|1|abbr=on}} thick, consisting of a pane of {{convert|25|mm|in|1|abbr=on|adj=on}} laminated glass, {{convert|25|mm|in|1|abbr=on}} airspace and a pane of {{convert|13|mm|in|1|abbr=on|adj=on}} laminated glass. In 2008, one elevator was upgraded to add a glass floor panel, believed to have the highest vertical rise of any elevator equipped with this feature.<ref>{{cite news|author=Canadian Press |author-link=Canadian Press |title=CN Tower's glass-floor elevator aims for record |url=https://www.thestar.com/News/GTA/article/412944 |work=Toronto Star |date=April 9, 2008 |access-date=April 9, 2008 |archive-url=https://web.archive.org/web/20091018091131/http://www.thestar.com/News/GTA/article/413153 |archive-date=October 18, 2009 |url-status=live |df=mdy}} Both linked pages include a video of the elevator with glass floor in operation.</ref> The Horizons Cafe and the lookout level are at {{convert|346|m|ft|1|abbr=on}}. The 360 Restaurant (formally "360 The Restaurant at the CN Tower"), a [[revolving restaurant]] that completes a full rotation once every 72 minutes, is at {{convert|351|m|ft|1|abbr=on}}. When the tower first opened, it also featured a discotheque named Sparkles (at the Indoor Observation Level), billed as the highest disco and dance floor in the world.<ref>Malcolm, Andrew. [https://select.nytimes.com/gst/abstract.html?res=FA0D10F73F5C11728DDDA90994D8415B898BF1D3 "A New High for Disco in Toronto's Tower"], ''[[The New York Times]]'', October 10, 1979. Accessed February 10, 2011.</ref>
 
The Top was once the highest public [[observation deck]] in the world until it was surpassed by the [[Shanghai World Financial Center]] in 2008.<ref name="swfc-e">{{cite web |title=Shanghai World Financial Center |url=http://www.emporis.com/en/wm/bu/?id=shanghaiworldfinancialcenter-shanghai-china |access-date=May 22, 2008 |publisher=Emporis.com |archive-url=https://web.archive.org/web/20080316224038/http://www.emporis.com/en/wm/bu/?id=shanghaiworldfinancialcenter-shanghai-china |archive-date=March 16, 2008 |url-status=usurped |df=mdy }}</ref>
 
A metal staircase reaches the main deck level after 1,776 steps,<ref name="great" /><ref name="CNSTEPS">{{cite news| title=Man climbs CN Tower steps in wheelchair |url=https://www.cbc.ca/news/canada/man-climbs-cn-tower-steps-in-wheelchair-1.316897 |work=[[CBC News]] |publisher=[[Canadian Broadcasting Corporation]] |date=September 27, 2002 |access-date=January 4, 2008 |archive-url=https://web.archive.org/web/20110130060357/http://www.cbc.ca/canada/story/2002/09/26/wheelchair_020926.html |archive-date=January 30, 2011 |url-status=live |df=mdy }}</ref> and The Top {{convert|100|m|ft|0|abbr=on}} above after 2,579 steps; it is the tallest metal staircase on Earth. These stairs are intended for emergency use only except for charity stair-climb events two times during the year.<ref name="WWFClimb">{{cite web |url=http://wwfcentral.ca/NetCommunity/Page.aspx?pid=500&srcid=500 |title=18th Annual Canada Life CN Tower Climb for WWF Canada |access-date=March 20, 2008 |publisher=[[World Wide Fund for Nature]] (WWF) Canada |archive-url=https://web.archive.org/web/20080324105225/http://wwfcentral.ca/NetCommunity/Page.aspx?pid=500&srcid=500 |archive-date=March 24, 2008 |url-status=dead |df=mdy-all }}</ref><ref name="TorontoStarSteps">{{cite news |first=Leslie |last=Ferenc |title=Corporate climbers ready to step up for charity |url=https://www.thestar.com/news/2007/10/15/corporate_climbers_ready_to_step_up_for_charity.html |work=Toronto Star |date=October 15, 2007 |access-date=March 20, 2008 |archive-url=https://web.archive.org/web/20081215182839/http://www.thestar.com/News/article/266851 |archive-date=December 15, 2008 |url-status=live |df=mdy }}</ref> The average climber takes approximately 30 minutes to climb to the base of the radome, but the fastest climb on record is 7 minutes and 52 seconds in 1989 by Brendan Keenoy, an [[Ontario Provincial Police]] officer.<ref name="TorontoStarSteps" /> In 2002, Canadian Olympian and [[Paralympic Games|Paralympic]] champion [[Jeff Adams]] climbed the stairs of the tower in a specially designed [[wheelchair]]. The stairs were originally on one of the three sides of the tower (facing north), with a glass view, but these were later replaced with the third elevator pair and the stairs were moved to the inside of the core.<ref name="CNSTEPS" /> Top climbs on the new, windowless stairwell used since around 2003 have generally been over ten minutes.<ref>{{cite web| title=21st Annual Canada Life CN Tower Climb for WWF-Canada| url=http://assets.wwf.ca/downloads/teamresults2011_overallindividuals.cfm| publisher=WWF| access-date=January 2, 2013| archive-url=https://web.archive.org/web/20110420064601/http://assets.wwf.ca/downloads/teamresults2011_overallindividuals.cfm| archive-date=April 20, 2011| url-status=dead}}</ref>
 
<gallery mode="packed" heights="135" style="text-align:left">
File:CN Tower, Toronto, Ontario (29969151776).jpg|Inside 360 Restaurant
File:CN Tower Main Observation Level 2023.jpg|Main Observation Level after renovation in 2018
File:CN Tower Turmkorb-Modell-blau.png|Cross-section of Main Pod
File:CN Tower SkyPod 2023g.jpg|The Top (SkyPod) in 2023
File:CN Tower SkyPod 2023i.jpg|Elevator at The Top level in 2023
File:CN Tower Terrace Level after renovation in 2023.jpg|Lower Observation Level glass floor
File:CNTowerNastyFall.jpg|View through glass floor
File:CN Tower Gift Shop after renovation 2023.jpg|Gift shop in 2023
File:CN Tower Ground View Looking Up.png|Ground view looking up at the CN Tower.
</gallery>
 
=== Architects ===
*[[WZMH Architects]]
*[[John Andrews (architect)|John Hamilton Andrews]]
*Webb Zerafa
*Menkes Housden with the help of Edward R. Baldwin
 
=== Falling ice danger ===
[[File:Gardiner Expressway Downtown Toronto.jpg|thumb|right|Looking east at CN Tower from [[Gardiner Expressway]] in 2010]]
 
A [[freezing rain]] storm on March 2, 2007, resulted in a layer of ice several centimetres thick forming on the side of the tower and other downtown buildings. The sun thawed the ice, then winds of up to {{convert|90|km/h|mph|0|abbr=on}} blew some of it away from the structure. There were fears that cars and windows of nearby buildings would be smashed by large chunks of ice. In response, police closed some streets surrounding the tower. During morning rush hour on March 5 of the same year, police expanded the area of closed streets to include the [[Gardiner Expressway]] {{convert|310|m|ft|0|abbr=on}} away from the tower as increased winds blew the ice farther, as far north as [[King Street (Toronto)|King Street West]], {{convert|490|m|ft|0|abbr=on}} away, where a [[taxi]]cab window was shattered. Subsequently, on March 6, 2007, the Gardiner Expressway reopened after winds abated.<ref>{{cite news |url=https://toronto.citynews.ca/2007/03/02/falling-cn-tower-ice/ |title=Video: Falling CN Tower Ice |publisher=[[CITY-DT]] |date=March 2, 2007 |access-date=June 26, 2007 |archive-url=https://web.archive.org/web/20090723053310/http://www.citynews.ca/news/features_8415.aspx |archive-date=July 23, 2009 |url-status=live |df=mdy }}</ref>
 
On April 16, 2018, falling ice from the CN Tower punctured the roof of the nearby [[Rogers Centre]] stadium, causing the [[Toronto Blue Jays]] to postpone the game that day to the following day as a [[Doubleheader (baseball)|doubleheader]]; this was the third doubleheader held at the Rogers Centre. On April 20 of the same year, the CN Tower reopened.<ref>{{cite web|url=http://www.cbc.ca/news/canada/toronto/cn-tower-closed-since-monday-due-to-falling-ice-concerns-reopens-1.4628235|title=CN Tower, closed since Monday due to falling ice concerns, reopens|date=20 April 2018|publisher=cbc.ca}}</ref>
 
=== Safety features ===
In August 2000, a fire broke out at the [[Ostankino Tower]] in Moscow, killing three people and causing extensive damage. The fire was blamed on poor maintenance and outdated equipment. The failure of the fire-suppression systems and the lack of proper equipment for firefighters allowed the fire to destroy most of the interior and sparked fears the tower might even collapse.
 
The Ostankino Tower was completed nine years before the CN Tower and is only {{convert|13|m|ft|abbr=on}} shorter.<ref name=doom>{{cite news|
url=https://www.independent.co.uk/news/world/europe/fire-in-1800ft-tv-tower-adds-to-russians-feeling-of-doom-5370409.html| title=Fire in 1,800ft TV tower adds to Russians' feeling of doom| first=Helen| last=Womackin| work=[[The Independent]]| date=August 29, 2000}}</ref> The parallels between the towers led to some concern that the CN Tower could be at risk of a similar tragedy. However, Canadian officials subsequently stated that it is "highly unlikely" that a similar disaster could occur at the CN Tower, as it has important safeguards that were not present in the Ostankino Tower. Specifically, officials cited:
 
* the fireproof building materials used in the tower's construction,
* frequent and stringent safety inspections,
* an extensive sprinkler system,
* a 24-hour emergency monitoring operation,
* two 68,160-litre (15,000-imperial gallon; 18,006-US gallon) water reservoirs at the top, which are automatically replenished,
* a fire hose at the base of the structure capable of sending {{Convert|2725|litres/min|U.S.gal/min impgal/min|abbr=on}} to any ___location in the tower,
* a ban on natural gas appliances anywhere in the tower (including the restaurant in the main pod),
* an elevator that can be used during a fire as it runs up the outside of the building and can be powered by three emergency generators at the base of the structure (unlike the elevator at the Ostankino Tower, which malfunctioned).<ref name="safety">{{cite news|url=https://www.cbc.ca/news/canada/what-if-the-cn-tower-caught-fire-1.217078 |date=November 10, 2000 |title=What if the CN Tower Caught Fire? |work=[[CBC News]] |publisher=[[Canadian Broadcasting Corporation]] |access-date=June 26, 2007 |archive-url=https://web.archive.org/web/20100327142807/http://www.cbc.ca/canada/story/2000/08/28/CN000828.html |archive-date=March 27, 2010 |url-status=live |df=mdy }}</ref>
 
Officials also noted that the CN Tower has an excellent safety record, although there was an electrical fire in the antennas on August 16, 2017 — the tower's first fire.<ref name="safety"/><ref name=Doherty>{{cite news| url=https://www.thestar.com/news/gta/2017/08/16/fire-crews-tackle-smouldering-fire-at-cn-tower-antenna.html| title=Fire crews tackle smouldering fire at CN Tower antenna| work=Toronto Star| date=August 16, 2017| first=Brennan| last=Doherty| agency=[[The Canadian Press]]| access-date=August 16, 2017| archive-date=August 16, 2017| archive-url=https://web.archive.org/web/20170816141642/https://www.thestar.com/news/gta/2017/08/16/fire-crews-tackle-smouldering-fire-at-cn-tower-antenna.html| url-status=dead}}</ref><ref>{{cite news| first=Amara| last=McLaughlin| url=http://www.cbc.ca/news/canada/toronto/cn-tower-fire-1.4249033| title=Fire inside broadcasting antenna atop CN Tower now extinguished| work=[[CBC News]]| date=August 16, 2017| access-date=August 17, 2017}}</ref><ref name=CTV>{{cite web| url=https://www.ctvnews.ca/toronto/article/cn-tower-open-for-business-after-early-morning-fire-in-antenna-mast/| title=CN Tower open for business after early morning fire in antenna mast| work=[[CFTO-DT|CTV Toronto News]]| first=Codi| last=Wilson| date=August 16, 2017| access-date=August 17, 2017}}</ref> Moreover, other supertall structures built between 1967 and 1976 — such as the [[Willis Tower]] (formerly the Sears Tower), the [[World Trade Center (1973–2001)|World Trade Center]] (until its [[September 11 attacks|destruction on September 11, 2001]]), the [[Fernsehturm Berlin]], the [[Aon Center (Chicago)|Aon Center]], 875 North Michigan Avenue (formerly the [[John Hancock Center]]), and First Canadian Place — also have excellent safety records, which suggests that the Ostankino Tower accident was a rare safety failure, and that the likelihood of similar events occurring at other supertall structures is extremely low.
 
{{wide image|Toronto panorama.jpg|1000px|Panorama as viewed from the CN Tower circa 2000: [[Toronto Islands]] and [[Billy Bishop Toronto City Airport|Bishop airport]] on Lake Ontario on left; [[Financial District, Toronto|Financial District]] on right}}
 
== Lighting ==
[[File:CN Tower lights in-memoriam to Paris attacks.JPG|thumb|upright|Illuminated in the colours of the [[Flag of France]] following the [[November 2015 Paris attacks]]]]
The CN Tower was originally lit at night with [[Incandescent light bulb|incandescent]] lights, which were removed in 1997 because they were inefficient and expensive to repair. In June 2007, the tower was outfitted with 1,330 super-bright LED lights inside the elevator shafts, shooting over the main pod and upward to the top of the tower's mast to light the tower from dusk until 2 a.m. the next calendar day. The official opening ceremony took place on June 28, 2007, before the [[Canada Day]] holiday weekend.
 
The tower changes its lighting scheme on holidays and to commemorate major events. After the [[95th Grey Cup]] in Toronto, the tower was lit in green and white to represent the colours of the Grey Cup champion [[Saskatchewan Roughriders]].<ref name="LED">{{cite press release| title=Highlighting the CN Tower — Testing of Innovative Illumination Technology Begins Early June 2007| publisher=CN Tower| date=June 28, 2007| url=http://www.cntower.ca/site_Files/.../CN_Tower_lighting_facts_2012.pdf| access-date=April 9, 2008}} {{dead link|date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> From sundown on August 27, 2011, to sunrise the following day, the tower was lit in orange, the official colour of the [[New Democratic Party]] (NDP), to commemorate the [[Death and state funeral of Jack Layton|death]] of federal NDP leader and leader of the official opposition [[Jack Layton]].<ref name=layton>{{cite news| title=Jack Layton's 'passion, civility' honoured at funeral| url=https://www.cbc.ca/news/canada/jack-layton-s-passion-civility-honoured-at-funeral-1.1001185| publisher=[[CBC News]]| access-date=August 28, 2011| date=August 27, 2011}}</ref> When former [[President of South Africa|South African president]] [[Nelson Mandela]] [[Death and state funeral of Nelson Mandela|died]], the tower was lit in the colours of the [[Flag of South Africa|South African flag]]. When former [[Minister of Finance (Canada)|federal finance minister]] under [[Stephen Harper]]'s [[Conservative Party of Canada|Conservatives]] [[Jim Flaherty]] died, the tower was lit in green to reflect his [[Irish Canadians|Irish Canadian]] heritage. On the night of the [[November 2015 Paris attacks|attacks on Paris on November 13, 2015]], the tower displayed the colours of the [[Flag of France|French flag]]. On June 8, 2021, the tower displayed the colours of the [[Toronto Maple Leafs]]' archrivals [[Montreal Canadiens]] after they advanced to the semifinals of [[2021 Stanley Cup playoffs]].<ref>{{cite web|url=https://www.tsn.ca/toronto-s-cn-tower-to-be-lit-in-montreal-canadiens-colours-on-tuesday-1.1651720|title=Toronto's CN Tower to be lit in Canadiens colours|author=TSN.ca Staff|work=[[The Sports Network|TSN]]|date=June 8, 2021|access-date=June 9, 2021}}</ref> The CN Tower was lit in the colours of the [[Flag of Ukraine|Ukrainian flag]] during the beginning of the [[Russian invasion of Ukraine]] in late February 2022. On June 4, 2025, the CN Tower was lit in the colours of the [[Edmonton Oilers]] for the [[2025 Stanley Cup Final]].
 
Programmed remotely from a [[desktop computer]] with a [[wireless network interface controller]] in [[Burlington, Ontario]], the LEDs use less energy to light than the previous incandescent lights (10% less energy than the dimly lit version and 60% less than the brightly lit version).<ref>{{cite news |url=https://www.thestar.com/news/2007/05/30/come_canada_day_cn_tower_will_once_again_light_up_the_night.html |title=Come Canada Day, CN Tower will once again light up the night |first=Debra |last=Black |date=May 30, 2007 |work=Toronto Star |access-date=July 17, 2011}}</ref> The estimated cost to use the LEDs is $1,000 per month.
 
During the spring and autumn [[bird migration]] seasons, the lights are turned off to comply with the voluntary Fatal Light Awareness Program, which "encourages buildings to dim unnecessary exterior lighting to mitigate bird mortality during spring and summer migration."<ref>{{cite web |url=http://www.ledsmagazine.com/news/4/6/21 |title=CN Tower in Toronto receives LED lighting treatment |work=LEDs Magazine |date=June 18, 2007 |access-date=July 17, 2011 |archive-url=https://web.archive.org/web/20111001092711/http://www.ledsmagazine.com/news/4/6/21 |archive-date=October 1, 2011 |url-status=dead }}</ref>
 
{| class="wikitable"
|-
! Date !! Colour !! Occasion
! Callsign !! Frequency !! Band !! Branding !! Notes
|-
| Ongoing || [[Red]] and [[White]] || Top of the hour CN Tower light show
| colspan="4"|Master FM || align="left"|Consortium of Toronto broadcasters for [[Digital audio broadcasting]]
|-
| January 26 || [[Shades of blue|Light Blue]] and [[Yellow]] || [[Alzheimer's disease|World Alzheimer Day]]
| [[CFMJ (AM)|CFMJ]] || 640 kHz || AM || AM640 Toronto Radio ||
|-
| February 4 || [[Orange (colour)|Orange]] and [[Blue]] || [[World Cancer Day]]
| [[CFMX-FM|CFMX]] || 96.3 MHz || FM || Classical 96 ||
|-
| February 14 || [[Red]] || [[Valentine's Day]]
| [[CFNY-FM|CFNY]] || 102.1 MHz || FM || 102.1 The Edge ||
|-
| March 17 || Green || [[Saint Patrick's Day]]
| [[CFRB (AM)|CFRB]] || 1010 kHz || AM || Newstalk 1010 ||
|-
| March 21–June 20 || Decreased Lighting || [[Bird migration|Bird Migration]] - Lighting is decreased during spring bird migration
| [[CFTR (AM)|CFTR]] || 680 kHz || AM || 680 News ||
|-
| September 23–December 20 || Decreased Lighting || Bird Migration - Lighting is decreased during autumn bird migration
| [[CHFI-FM|CHFI]] || 98.1 MHz || FM || 98.1 CHFI ||
|-
| December || [[Red]] and [[Green]] || [[Christmas and holiday season|Season's Greetings]]
| [[CHIN-FM|CHIN]] || 100.7 MHz || FM || CHIN Radio || align="left"|Primarily in Italian and Portuguese
|-
| December 1 || [[Red]] || [[World AIDS Day]]
| [[CHIN (AM)|CHIN]] || 1540 kHz || AM || CHIN Radio || align="left"|Primarily in Italian and Cantonese
|-
| December 6 || [[Purple]] || [[National Day of Remembrance and Action on Violence Against Women|White Ribbon Day]]
| [[CHUM-FM|CHUM]] || 104.5 MHz || FM || 104.5 CHUM FM ||
|-
| December 10 || [[Yellow]] || [[Human Rights Day]]
| [[CHUM (AM)|CHUM]] || 1050 kHz || AM || 1050 CHUM ||
|-
| December 21 || [[Blue]] and [[White]] || [[Winter solstice|First Day of Winter]]
| [[CHWO (AM)|CHWO]] || 740 kHz || AM || Prime Time Radio ||
|-
| December 31 || Countdown to {{NEXTYEAR}} and Light Show || [[New Year's Eve]]
| [[CIAO (AM)|CIAO]] || 530 kHz || AM || AM 530 Multicultural Radio || align="left"|Broadcasts from [[Brampton, Ontario]]
|}
 
== Height comparisons ==
[[File:CN Tower seen from its base.jpg|thumb|left|upright|View from base]]
[[File:Dubai-CN-Sears-towers.svg|thumb|upright|• [[Burj Khalifa]], Dubai<br />• CN Tower, Toronto<br />• [[Willis Tower]], Chicago]]
{{tallest towers in the world.svg|cu}}
The CN Tower is the tallest freestanding structure in the Western Hemisphere. As of 2013, there were two other [[List of tallest freestanding structures|freestanding structures in the Western Hemisphere]] exceeding {{convert|500|m|ft|1|abbr=on}} in height: the Willis Tower in Chicago, which stands at {{convert|527|m|ft|1|abbr=on}} when measured to its pinnacle, and [[One World Trade Center]] in New York City, which has a pinnacle height of {{convert|541.33|m|ft|1|abbr=on}}, or approximately {{convert|12|m|ft|1|abbr=on}} shorter than the CN Tower. Due to the symbolism of the number 1776 (the year of the signing of the [[United States Declaration of Independence]]), the height of One World Trade Center is unlikely to be increased. The proposed [[Chicago Spire]] was expected to exceed the height of the CN Tower, but its construction was halted early due to financial difficulties amid the [[Great Recession]], and was eventually cancelled in 2010.<ref>{{cite news| url=http://www.businessweek.com/innovate/next/archives/2010/02/calatrava_dances_onto_a_new_stage.html| title=Calatrava Dances onto a New Stage| work=[[Bloomberg Businessweek]]| url-status=dead| archive-url=https://web.archive.org/web/20110213045741/http://www.businessweek.com/innovate/next/archives/2010/02/calatrava_dances_onto_a_new_stage.html| archive-date=February 13, 2011| df=mdy-all}}</ref>
 
=== Height distinction debate ===
 
==== "World's Tallest Tower" title ====
''[[Guinness World Records]]'' has called the CN Tower "the world's tallest self-supporting tower" and "the world's tallest free-standing tower".<ref name="Guinness 1982">
{{cite book| last=McWhirter| first=Norris| author-link=Norris McWhirter| title=Guinness Book of World Records 1982| year= 1981| publisher=[[Sterling Publishing|Sterling Publishing Co., Inc.]]| ___location= New York| isbn=978-0-8069-0225-8|oclc=7902975| page=704}} Reference is on page 275.</ref><ref name="Guinness 2005">{{cite web |url=http://www.guinnessworldrecords.com/content_pages/record_subcategory.asp?txtDirection=right&;txtButtonWasHit=true&txtPage=4&subcategoryid=37 |title=Guinness Book of World Records 2005 – Science and Technology << Buildings |access-date=2010-01-05 |url-status=dead |archive-url=https://web.archive.org/web/20110826071440/http://www.guinnessworldrecords.com/content_pages/record_subcategory.asp?txtDirection=right&%3BtxtButtonWasHit=true&txtPage=4&subcategoryid=37 |archive-date=August 26, 2011 }}</ref> Although Guinness did list this description of the CN Tower under the heading "tallest building" at least once,<ref name="Guinness 2005"/> it has also listed it under "tallest tower", omitting it from its list of "tallest buildings."<ref name="Guinness 1982"/> In 1996, Guinness changed the tower's classification to "World's Tallest Building and Freestanding Structure". [[Emporis]] and the [[Council on Tall Buildings and Urban Habitat]] both listed the CN Tower as the [[List of tallest buildings and structures|world's tallest free-standing structure on land]], and specifically state that the CN Tower is not a true building, thereby awarding the title of [[List of tallest buildings|world's tallest building]] to [[Taipei 101]], which is {{convert|44|m|ft|0|abbr=on}} shorter than the CN Tower.<ref name="info"/><ref name=CTBUH>{{cite web |url=http://www.ctbuh.org/Resources/TallestDatabase/tabid/123/Default.aspx |title=CTBUH Tall Building Database |access-date=April 10, 2008 |publisher=[[Council on Tall Buildings and Urban Habitat]] |archive-url=https://web.archive.org/web/20081025030731/http://www.ctbuh.org/Resources/TallestDatabase/tabid/123/Default.aspx |archive-date=October 25, 2008 |url-status=dead |df=mdy }}</ref> The issue of what was tallest became moot when Burj Khalifa, then under construction, exceeded the height of the CN Tower in 2007 (see below).
 
Although the CN Tower contains a restaurant, a gift shop and multiple observation levels, it does not have floors continuously from the ground, and therefore [[List of tallest buildings and structures#Tallest buildings|it is not considered a building]] by the Council on Tall Buildings and Urban Habitat (CTBUH) or Emporis. CTBUH defines a building as "a structure that is designed for residential, business, or manufacturing purposes. An essential characteristic of a building is that it has floors."<ref name=CTBUH/> The CN Tower and other similar structures—such as the Ostankino Tower in Moscow, Russia; the [[Oriental Pearl Tower]] in [[Shanghai]], China; [[The Strat]] in [[Las Vegas]], Nevada, United States; and the [[Eiffel Tower]] in [[Paris]], France—are categorized as "towers", which are free-standing structures that may have observation decks and a few other habitable levels, but do not have floors from the ground up. The CN Tower was the tallest tower by this definition until 2010 (see below).<ref name="info"/>
 
Taller than the CN Tower are numerous [[radio masts and towers]], which are held in place by [[guy-wire]]s, the tallest being the [[KVLY-TV mast]] in [[Blanchard, North Dakota]], in the United States at {{convert|628|m|ft|0|abbr=on}} tall, leading to [[List of tallest structures|a distinction]] between these and "free-standing" structures. Additionally, the [[Petronius (oil platform)|Petronius Platform]] stands {{convert|610|m|ft|0|abbr=on}} above its base on the bottom of the [[Gulf of Mexico]]<!--Don't rename to Gulf of America--> near the [[Mississippi River Delta]], but only the top {{convert|75|m|ft|0|abbr=on}} of this [[oil platform|oil and natural gas platform]] are above water, and the structure is thus partially supported by its [[buoyancy]]. Like the CN Tower, none of these taller structures are commonly considered buildings.
 
On September 12, 2007, Burj Khalifa, which is a hotel, residential and commercial building in [[Dubai]], United Arab Emirates (formerly known as Burj Dubai before opening), passed the CN Tower's 553.33-m<ref name="CNTower"/> height. The CN Tower held the record of the tallest freestanding structure on land for over 30 years.<ref name="CBCSurpassed" />
 
After Burj Khalifa had been formally recognized by the Guinness World Records as the world's tallest freestanding structure, Guinness re-certified CN Tower as the world's tallest freestanding tower.<ref>{{cite news|url=https://www.thestar.com/news/gta/article/698891 |title=CN tower now the 'world's tallest freestanding tower' |last=Daubs |first=Katie |date=September 22, 2009 |work=Toronto Star |access-date=September 22, 2009 |archive-url=https://web.archive.org/web/20090927021016/http://www.thestar.com/News/GTA/article/698891 |archive-date=September 27, 2009 |url-status=live |df=mdy }}</ref> The tower definition used by Guinness was defined by the Council on Tall Buildings and Urban Habitat as 'a building in which less than 50% of the construction is usable floor space'. ''Guinness World Records'' editor-in-chief Craig Glenday announced that Burj Khalifa was not classified as a tower because it has too much usable floor space to be considered to be a tower.<ref>{{cite web| url=http://network.nationalpost.com/np/blogs/toronto/archive/2009/09/18/326566.aspx| title=CN Tower remains world's tallest tower, Guinness says| work=[[National Post]]| date=September 18, 2009}} {{dead link|date=August 2017}}</ref> CN Tower still held world records for highest above ground wine cellar (in 360 Restaurant) at 351 m, highest above-ground restaurant at 346 m (Horizons Restaurant),<ref>{{cite web| date=September 18, 2009| url=http://www.cbc.ca/news/canada/toronto/cn-tower-still-world-s-tallest-guinness-1.813395| title=CN Tower still world's tallest: Guinness| publisher=[[CBC News]]}}</ref> and tallest free-standing concrete tower during Guinness's recertification. The CN Tower was surpassed in 2009 by the [[Canton Tower]] in [[Guangzhou]], China, which stands at {{convert|604|m|ft|abbr=on}} tall, as the world's tallest tower; which in turn was surpassed by the [[Tokyo Skytree]] in 2011, which currently is the tallest tower at {{convert|634.0|m|ft|abbr=on}} in height.<ref name=canton/><ref>{{cite web| url=http://news.nationalgeographic.com/news/travelnews/2011/11/111128-worlds-tallest-tower-tokyo-travel/| archive-url=https://web.archive.org/web/20111129192458/http://news.nationalgeographic.com/news/travelnews/2011/11/111128-worlds-tallest-tower-tokyo-travel/| url-status=dead| archive-date=November 29, 2011| title=World's Tallest Tower Rises in Tokyo| date=November 29, 2011| last=Owen| first=James| work=[[National Geographic|National Geographic News]]}}</ref> The CN Tower, as of 2022, stands as the tenth-tallest free-standing structure on land, remains the tallest free-standing structure in the [[Western Hemisphere]], and is the third-tallest tower.<ref name=tallest/><ref>{{cite web|url=https://www.worldatlas.com/articles/10-tallest-towers-in-the-world.html|title=Where Is The Largest Tower In The World?|publisher=worldatlas.com|date=4 October 2018}}</ref><ref>{{Cite web |title=The CN Tower, once the world's tallest, soon won't even make the top 10 |url=https://nationalpost.com/news/the-cn-tower-once-the-worlds-tallest-soon-wont-even-make-the-top-10 |access-date=2023-01-22 |website=National Post |language=en-CA}}</ref> The CN Tower is the second-tallest free-standing structure in the [[Commonwealth of Nations]] behind [[Merdeka 118]] in [[Kuala Lumpur]], [[Malaysia]].
 
==== Height records ====
[[File:Rogers Center-restitched.jpg|thumb|upright|View from interior of [[Rogers Centre]]]]
 
Since its construction, the tower has gained the following world height records:<ref name=records>{{cite web| url=http://www.cntower.ca/about_us/awards_and_records/records/| title=The Tower, according to Guinness World Records| publisher=CN Tower| access-date=September 22, 2009| archive-date=November 18, 2009| archive-url=https://web.archive.org/web/20091118195948/http://www.cntower.ca/about_us/awards_and_records/records/| url-status=dead}}</ref>
{| class="wikitable"
|-
!Record
| [[CIRC (AM)|CIRC]] || 1610 kHz || AM || -- || align="left"|Proposed sister station of [[CIRV-FM]]
!Owner
!Value
!Time period
!Succeeded by
|-
|World's tallest free-standing structure||CN Tower||{{convert|553.33|m|ft}}||March 31, 1975 to September 12, 2007||[[Burj Khalifa]]
| [[CILQ-FM|CILQ]] || 107.1 MHz || FM || Q107 ||
|-
|World's tallest tower||CN Tower||{{convert|553.33|m|ft}}||1975 to 2009|| rowspan=2 |[[Canton Tower]]
| [[CKFM-FM|CKFM]] || 99.9 MHz || FM || Mix FM ||
|-
|World's highest public observation gallery||The Top||{{convert|447|m|ft}}|||
| [[CJAQ-FM|CJAQ]] || 92.5 MHz || FM || 92.5 JACK FM ||
|-
|World's highest glass floor panelled elevator||CN Tower||{{convert|346|m|ft}}||2008 to present||—
| [[CJCL (AM)|CJCL]] || 590 kHz || AM || The Fan 590 ||
|-
|World's longest metal staircase||CN Tower||2,579 steps||||
| [[CJEZ-FM|CJEZ]] || 97.3 MHz || FM || EZ Rock 97.3 ||
|-
|World's highest glass floor||CN Tower||{{convert|342|m|ft}}||2008 to July 2, 2009||[[Willis Tower]]
| [[CJMR (AM)|CJMR]] || 1320 kHz || AM || -- || align="left"|Ethnic Chinese Christian radio in [[Mississauga, Ontario]]
|-
|World's highest and largest revolving restaurant||360 Restaurant||{{convert|351|m|ft}}||||
| [[CJRT-FM|CJRT]] || 91.1 MHz || FM || JAZZ.FM91 ||
|-
|World's highest bar||Horizons Restaurant||{{convert|346|m|ft}}||September 21, 2009 to present||—
|-
|World's highest wine cellar||360 Restaurant||{{convert|351|m|ft}}||||
|}
 
== Use ==
===Cellular and paging providers===
[[File:Toronto - ON - CN Tower - Antennenspitze.jpg|thumb|upright|Main Pod and broadcast antennas]]
* [[Bell Mobility]]
The CN Tower has been and continues to be used as a communications tower for a number of different media and by numerous companies.<ref name="vividcomm">{{cite web |url=https://vividcomm.com/2019/09/25/cn-tower/ |title=CN Tower: RF Telecom |first=M.J. |last=Martin |date=September 25, 2019 |accessdate=June 3, 2023}}</ref>
* [[Rogers Wireless]]
* [[Motorola]]
 
=== Television broadcasters ===
===Communications===
{| class="wikitable sortable"
* [[Bell Canada]]
|-
* [[Toronto Transit Commission]]
<!-- !Frequency -->
* [[Amateur radio]] [[repeater]]s "2-Tango" (2 meter [[VHF]]) and "4-Tango" (440/70 cm [[UHF]]) &ndash; owned and operated by the Toronto FM Communications Society, under callsign VE3TWR.<ref name="ARES">
!VHF
{{cite web
!UHF
|url=http://ares.meskes.ca/frequencies.html
!Virtual
|title=Toronto ARES Channels
!Callsign
|accessdate=2006-08-03
!Affiliation
|date=[[2005-10-26]]
!Branding
}}</ref>
|-
<!-- |186.31 MHz -->
|9
|—
|9.1
|[[CFTO-DT]]
|[[CTV Television Network|CTV]]
|CTV Toronto
|-
<!-- |501.31 MHz -->
|—
|19
|19.1
|CICA-DT
|[[TVO]]
|TVO
|-
<!-- |507.31 MHz -->
|—
|20
|5.1
|[[CBLT-DT]]
|[[CBC Television]]
|CBC Toronto
|-
<!-- |537.31 MHz -->
|—
|25
|25.1
|[[CBLFT-DT]]
|[[Ici Radio-Canada Télé]]
|ICI Ontario
|-
<!-- | *FREQUENCY NEEDED* -->
|—
|40
|40.1
|[[CJMT-DT]]
|[[Omni Television]]
|Omni Television
|-
<!-- |633.31 MHz -->
|—
|41
|41.1
|[[CIII-DT]]
|[[Global Television Network|Global]]
|Global Toronto
|-
<!-- |651.31 MHz -->
|—
|44
|57.1
|[[CITY-DT]]
|[[Citytv]]
|Citytv Toronto
|-
<!-- |669.31 MHz -->
|—
|47
|47.1
|[[CFMT-DT]]
|[[Omni Television]]
|Omni Television
|-
| colspan="6" style="text-align: center;" | '''Source:''' Vividcomm<ref name="vividcomm"/>
|}
 
==Facts= andRadio figures===
{{see also|List of radio stations in Ontario}}
[[Image:DSCN4373.JPG|thumb|325px|right|The CN Tower, as seen from [[Trinity Bellwoods Park]] on the west side of [[Toronto]]]]
 
There is no [[AM broadcasting]] from the CN Tower.<ref>{{cite web| url=http://www.fcc.gov/fcc-bin/amq?state=ON&call=&arn=&city=Toronto&freq=530&fre2=1700&type=0&facid=&class=&list=1&dist=15&dlat2=43&mlat2=38&slat2=30.67&NS=N&dlon2=79&mlon2=23&slon2=14.27&EW=W&size=9| title=AM Query & AM List Results| access-date=April 9, 2008| date=April 9, 2008| publisher=[[Federal Communications Commission]] – Audio Division| archive-url=https://archive.today/20120801053741/http://www.fcc.gov/fcc-bin/amq?state=ON&call=&arn=&city=Toronto&freq=530&fre2=1700&type=0&facid=&class=&list=1&dist=15&dlat2=43&mlat2=38&slat2=30.67&NS=N&dlon2=79&mlon2=23&slon2=14.27&EW=W&size=9| archive-date=August 1, 2012| url-status=dead| df=mdy-all}}</ref> The [[FM broadcasting|FM]] transmitters are situated in a {{convert|102|m|ft|abbr=on|adj=mid|-tall}} metal broadcast antenna, on top of the main concrete portion of the tower at an elevation above {{convert|446.5|m|ft|abbr=on}} from the ground.
*The CN Tower is 13 metres taller than [[Moscow]]'s [[Ostankino Tower]], is almost twice as tall as the [[Eiffel Tower]], and is the tallest member of the [[World Federation of Great Towers]].
*The CN Tower is struck by [[lightning]] over 78 times a year.
*One person died during the building of the CN Tower.
*The CN Tower has a wind tolerance level of 420 km/h (260 mph).
*The elevators ascend and descend at over 22 km/h (15 mph), taking 58 seconds to reach the Lookout (indoor observation deck) and 61 seconds to reach the 360 restaurant levels respectively.
*The Glass Floor can withstand 4,100 kPa (600 lbs/sq in) or the equivalent to 14 adult [[hippopotami]].
*In winds of 120 mph the tower sways 1.07 m (3½ ft) from centre at the Antenna, 0.46 m (1½ ft) from centre at the Space Deck, and 22.9 cm (9 inches) from centre at the Sky Pod.
*The CN Tower weighs 117,910 metric tonnes (130,000 tons) as much as 20,000 elephants, and was built using 40,524 m³ (53,000 cu. yd.) of concrete, enough to build a sidewalk from Toronto to [[Kingston, Ontario]], about 250 km (155.3 mi) away.
*A [[Sikorsky Aircraft Corporation|Sikorsky]] [[CH-54 Tarhe|Skycrane]] [[helicopter]] nicknamed 'Olga' was used to lower the communications antenna into place on the tower. The helicopter was piloted by Larry Pravecek.
*The CN Tower is designed to withstand an earthquake of 8.5 on the Richter Scale.
*In 1979, Norman Alexander and Joe Squire hauled a 440 lb. piano up the stairs in 7½ hours.
*On [[July 23]], [[1999]], [[Ashrita Furman]] became the fastest person to go up the CN Tower using a [[pogo stick]].
*In 2001, a group of [[environmentalist]]s illegally scaled the outside of the Tower, in order to place a banner protesting the policies of [[United States]] [[President of the United States of America|President]] [[George W. Bush]].
*The tower is the only [[landmark]] from Canada that appears in the [[City-building game|city-building]]/[[simulation]] [[computer game]]s ''[[SimCity 3000]]'' and ''[[SimCity 4]]''.
*The CN Tower was included in the [[Namco]] pilot simulation game [[Ace Combat 5: The Unsung War]]. The tower rests in a fictional metropolitan area named [[November City]].
*The tower is occasionally mistaken by some for the [[Seattle]] [[Space Needle]], due to their similar appearances. While filming in Toronto, American talk show host [[Conan O'Brien]] staged a mock fight on his show between two men costumed as the respective towers.
*The CN Tower can be accidentally seen numerous times during scenes in the [[Police Academy]] series.
*The CN Tower celebrated 30 years as the world's tallest freestanding tower on June 26, 2006.
*The tower was featured in the 1995 film ''[[Canadian Bacon (film)|Canadian Bacon]]''.
*The song "''The CN Tower Belongs to the Dead''" by [[Owen Pallett]] obviously references the Tower.
*The CN Tower was featured on the front cover of the [[1996]] ''[[Guinness Book of World Records]]''<ref name="CNAA">{{cite web
|url=http://www.cntower.ca/portal/SmartDefault.aspx?at=898
|title=Awards and Achievements
|accessdate=2006-08-01
|work=CN Tower
}}</ref>.
*The CN Tower is featured in the music video of ''[[Another Postcard]]'', a song on the [[2003 in music|2003]] ''[[Everything to Everyone]]'' album by the [[Barenaked Ladies]].
*In April [[2006]], Braden Fox, a [[Humber College]] [[firefighting]] student climbed the stairs in full turnout gear to raise money for the [[WWF (conservation organization)|World Wide Fund for Nature]] (WWF). His time of 20 minutes 43 seconds beat the previous record for such a feat by over two full minutes.
 
{| class="wikitable sortable"
==See also==
!Frequency
*[[Tallest free standing structure on land]]
!kW
*[[List of towers]]
!Callsign<ref>{{cite web| url=http://www.fcc.gov/fcc-bin/fmq?state=&call=&city=&arn=&serv=&vac=&freq=0.0&fre2=107.9&facid=&class=&dkt=&list=1&dist=10&dlat2=43&mlat2=38&slat2=30.67&NS=N&dlon2=79&mlon2=23&slon2=14.27&EW=W&size=9| title=FM Query & FM List Results| access-date=April 9, 2008| date=April 9, 2008| publisher=Federal Communications Commission – Audio Division| archive-url=https://archive.today/20120802213851/http://www.fcc.gov/fcc-bin/fmq?state=&call=&city=&arn=&serv=&vac=&freq=0.0&fre2=107.9&facid=&class=&dkt=&list=1&dist=10&dlat2=43&mlat2=38&slat2=30.67&NS=N&dlon2=79&mlon2=23&slon2=14.27&EW=W&size=9| archive-date=August 2, 2012| url-status=dead| df=mdy-all}}</ref>
*[[List of masts]]
!Affiliation/Owner
*[[List of skyscrapers]]
!Branding
*[[List of tallest structures in Canada]]
!Notes
*[[World's tallest structures]]
|-
*[[Cityplace (Toronto)]]
|91.1&nbsp;MHz
|40
|[[CJRT-FM|CJRT]]
|Independent; [[Public radio|Public]]
|JAZZ.FM91
|[[Jazz]]
|-
|94.1&nbsp;MHz
|38
|[[CBL-FM|CBL]]
|[[Canadian Broadcasting Corporation]]
|[[CBC Music]]
|Non-commercial; [[Classical music|classical]]; jazz
|-
|97.3&nbsp;MHz
|28.9
|[[CHBM-FM|CHBM]]
|[[Stingray Group]]
|boom 97.3
|[[Classic hits]]
|-
|98.1&nbsp;MHz
|44
|[[CHFI-FM|CHFI]]
|[[Rogers Sports & Media]]
|98.1 CHFI
|[[Adult contemporary music|Adult contemporary]]
|-
|99.9&nbsp;MHz
|40
|[[CKFM-FM|CKFM]]
|[[Bell Media]]
|Virgin Radio 99.9FM
|[[Contemporary hit radio|Top 40/Contemporary hits]]
|-
|100.7&nbsp;MHz
|4
|[[CHIN-FM|CHIN]]
|[[CHIN Radio/TV International]]
|CHIN Radio
|Primarily in [[Italian language|Italian]] and [[Portuguese language|Portuguese]]
|-
|102.1&nbsp;MHz
|35
|[[CFNY-FM|CFNY]]
|[[Corus Entertainment]]
|102.1 the Edge
|[[Alternative rock]]
|-
|104.5&nbsp;MHz
|40
|[[CHUM-FM|CHUM]]
|[[Bell Media]]
|104.5 CHUM FM
|[[Hot adult contemporary]]<!--Don't bypass redirect per [[WP:NOTBROKEN]]-->
|-
|107.1&nbsp;MHz
|40
|[[CILQ-FM|CILQ]]
|[[Corus Entertainment]]
|Classic Rock Q 107
|[[Mainstream rock]]
|-
| colspan="6" style="text-align: center;" | '''Source:''' Vividcomm<ref name="vividcomm"/>
|}
 
=== Communications ===
==References==
* [[Bell Canada]]
<!--<nowiki>
* [[Toronto Transit Commission]]
See http://en.wikipedia.org/wiki/Wikipedia:Footnotes for an explanation of how
* [[Amateur radio]] [[repeater]]s "2-Tango" ([[Very high frequency|VHF]]) and "4-Tango" (440/70&nbsp;cm [[Ultra high frequency|UHF]])—owned and operated by the Toronto FM Communications Society, under callsign VE3TWR<ref name="ARES">{{cite web |url=http://ares.meskes.ca/frequencies.html |title=Toronto ARES Channels |access-date=August 3, 2006 |date=October 26, 2005}}</ref>
to generate footnotes using the <ref> and </ref> tags, and the template below
</nowiki>-->
{{FootnotesSmall|resize=90%}}
 
== In popular culture ==
==External links==
The CN Tower has been featured in numerous films, television shows, music recording covers, and video games. The tower also has its own official mascot, which resembles the tower itself.<ref>{{cite web| url=https://www.thestar.com/news/gta/2017/07/19/a-new-mascot-for-the-cn-tower-is-a-mini-cn-tower.html| title=A new mascot for the CN Tower is a mini CN Tower| last=Fearon| first=Emily| date=July 19, 2017| work=Toronto Star}}</ref>
{{Commonscat|CN Tower}}
<!--Before adding a work, please discuss on the talk page; consensus must be reached-->
*[http://www.cntower.ca/ Official site of the CN tower]
*''[[Highpoint (film)|Highpoint]]'' is a Canadian 1982 action film starring [[Richard Harris]], [[Christopher Plummer]] and [[Beverly D'Angelo]]. It features a shot of stuntman [[Dar Robinson]] jumping off of the CN Tower in 1979.<ref name="robinson"/>
*[http://www.guinnessworldrecords.com/content_pages/record.asp?recordid=49675 Guinness entry for the CN Tower]
*''[[Views (album)|Views]]'' is a 2016 studio album released on April 29, 2016, by Canadian rapper [[Drake (musician)|Drake]]. The cover artwork features Drake sitting atop the CN Tower in Toronto.<ref>{{cite web|url=https://www.thestar.com/entertainment/2016/04/26/drakes-towering-view-of-the-6.html|title=Drake's towering view of The 6 {{!}} Toronto Star|website=thestar|date=April 26, 2016|access-date=July 11, 2016|url-status=live|archive-url=https://web.archive.org/web/20160816134609/https://www.thestar.com/entertainment/2016/04/26/drakes-towering-view-of-the-6.html|archive-date=August 16, 2016|df=mdy-all}}</ref> Drake appeared significantly larger than life-size on the cover, and the CN Tower's [[Twitter]]<!--Don't replace with X as the tweet was made before Elon Musk purchased the website and rebranded it--> account later confirmed it to be [[Photograph manipulation|photo edited]].<ref>{{cite tweet|user=TourCNTower|number=724591858190573568|date=April 25, 2016|title=Proud Torontonian @Drake at the top of CN Tower with the help of some photoshop magic! #photshopped #notreallythere|url-status=live|archive-url=https://archive.today/20160428111103/https://twitter.com/TourCNTower/status/724591858190573568|archive-date=April 28, 2016}}</ref>
*[http://www.xs4all.nl/~hnetten/tallest.html What is the tallest building in the world?]
<!--Before adding a work, please discuss on the talk page; consensus must be reached-->
*[http://maps.google.ca/maps?ll=43.641987,-79.387110&spn=0.005891,0.005789&t=k&hl=en Google Satellite Image]
*[http://bbs.keyhole.com/ubb/showthreaded.php/Cat/0/Number/438474/an/0/page/0#438474 CN Tower in 3D on Google Earth]
*[http://skyscraperpage.com/diagrams/?c12 25 Tallest Buildings in Toronto]
*[http://www.emporis.com/en/wm/bu/?id=112537 Emporis CN Tower listing]
 
== See also ==
{{coor title dms|43|38|33.24|N|79|23|13.7|W|}}
{{Portal|Architecture|Canada|Ontario}}
* [[Architecture of Toronto]]
* [[List of tallest buildings in Toronto]]
* [[List of tallest structures in Canada]]
* [[List of tallest structures]]
* [[List of tallest towers]]
* [[List of tallest buildings and structures]]
* [[List of tallest structures]]
 
== References ==
{{Reflist|30em}}
 
== External links ==
{{Commons category|CN Tower}}
* {{official website|https://www.cntower.ca/}}
* [https://www.cbc.ca/player/play/video/1.3581406 CBC Archives – CN Tower opens to the public]
* [http://www.edgewalkcntower.ca/ Edgewalk]
* [http://www.pastandfuturehistory.com/ The Design, Engineering and Construction of the CN Tower – 1972 through to 1976]
* [https://www.flickr.com/photos/40744368@N04/sets/72157632200955200/ A visual construction history of the CN Tower – at 40th year anniversaries]
* [https://www.flickr.com/photos/40744368@N04/sets/72177720324980183/ The Design, Engineering & Construction History of the CN Tower and the People Who Built it]
* [https://www.youtube.com/watch?v=K67j5juf-V4 How the CN Tower was Built]—Art of Engineering ([[YouTube]] documentary)
 
{{S-start}}
{{S-ach|rec}}
{{s-bef|rows=2|before=[[Ostankino Tower]]}}
{{s-ttl|title=[[History of the world's tallest structures#Freestanding structures|World's tallest free-standing structure]]<br /><small>553.33 m (1,815 ft 5 in)</small>|years= 1975–2007}}
{{s-aft|after=[[Burj Khalifa]]}}
{{s-ttl|title=[[History of the world's tallest structures#Freestanding towers|World's tallest free-standing tower]]|years= 1975–2010}}
{{s-aft|after=[[Canton Tower]]}}
{{S-end}}
{{Toronto landmarks}}
{{Toronto skyscrapers}}
{{Supertall observation and communication towers}}
{{Supertall}}
 
{{DEFAULTSORT:Cn Tower}}
[[Category:1976 architecture]]
[[Category:Towers1976 establishments in CanadaOntario]]
[[Category:Articles containing video clips]]
[[Category:Buildings and structures in Toronto]]
[[Category:TourismCanadian inNational CanadaRailway facilities]]
[[Category:RevolvingCommunication restaurantstowers in Canada]]
[[Category:Former world's tallest buildings]]
 
[[Category:Modernist architecture in Canada]]
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[[Category:Observation towers in Canada]]
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[[esCategory:TorreRailway CNLands]]
[[Category:Stairways]]
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[[Category:Tourist attractions in Toronto]]
[[fr:Tour CN]]
[[Category:Towers completed in 1976]]
[[ko:CN 타워]]
[[Category:Towers in Ontario]]
[[io:Turmo nacionala di Kanada]]
[[Category:Towers with revolving restaurants]]
[[id:Menara CN]]
[[Category:Transmitter sites in Canada]]
[[he:מגדל סי אן]]
[[Category:WZMH Architects buildings]]
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[[pt:Torre CN]]
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[[vi:Tháp CN]]
[[zh:加拿大国家电视塔]]