On steep mountain walls, sections of rock may bulge beyond vertical to form an overhang. If an overhang juts horizontally from the adjacent face, it is called a ceiling or roof—for example, the Great Roof on El Capitan, which casts a shadow across the monolith’s south buttress like an immense granite awning that hangs two thousand feet above the meadows of Yosemite Valley.

Jon Krakauer