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[[File:Ende Gelände 2017 CHB 23 (cropped).jpg|thumb|The giant [[bucket-wheel excavator]]s in the German Rhineland coal mines are among the world's biggest land vehicles.]]
'''Open-pit mining''', also known as '''open-cast''' or '''open-cut mining''' and in larger contexts '''mega-mining''',<ref>{{Cite web|last=Serafini|first=Paula|title=The Argentinian fight against 'mega mining'|url=http://theconversation.com/the-argentinian-fight-against-mega-mining-95672|access-date=2021-04-22|website=The Conversation|date=4 May 2018 }}</ref> is a [[surface mining]] technique
This form of [[mining]] differs from extractive methods that require tunnelling into the earth, such as [[long wall mining]]. Open-pit mines are used when deposits of commercially useful ore or rocks are found near the surface. It is applied to ore or rocks found at the surface because the [[overburden]] is relatively thin or the material of interest is structurally unsuitable for tunnelling (as would be the case for cinder, sand, and gravel). In contrast, minerals that have been found underground but are difficult to retrieve due to hard rock, can be reached using a form of underground mining.<ref>{{Cite book|url=https://www.nap.edu/read/10318/chapter/5|title=Read "Evolutionary and Revolutionary Technologies for Mining" at NAP.edu|year=2002|doi=10.17226/10318|isbn=978-0-309-07340-0}}</ref>
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