For 10 points, name this extreme sport in which absolute maniacs gain intimate geographical knowledge of places such as Ben Nevis or Mount Everest.
People who do this rigorously in Scotland are said to have gone "Munro bagging" and are at risk of encountering a cryptid known as the "Big Grey Man." Practitioners of this pastime should be wary of Brocken spectres, caused by an optical illusion that magnifies the size of one's own shadow. Side effects of performing this action are treated in South America by chewing medicinal coca leaves. People attempting a feat in this activity might rely on (*) landmarks such as "Green Boots," the epithet of a person who froze to death while doing this. A particularly well-known person involved in this activity, when asked about his motivations for performing it, responded, "Because ► it's there." For 10 points, name this extreme sport in which absolute maniacs gain intimate geographical knowledge of places such as Ben Nevis or Mount Everest.
People who do this rigorously in Scotland are said to have gone "Munro bagging" and are at risk of encountering a cryptid known as the "Big Grey Man."
mountain climbing [or obvious equivalents; if player gives more specific answer than necessary, ask for less specificity or accept outright at own leisure]