cave
Also known as a cavern, a natural underground space large enough for a human to enter. Caves form naturally by the weathering of rock and they often extend deep underground. The word "cave" can also refer to much smaller openings such as sea caves, rock shelters, and grottos.
See also
The following tags are aliased to this tag: caves (learn more).
The following tags implicate this tag: cave_entrance and cave_interior (learn more).