is 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.
Throughout history, people have made use of caves for shelter, burial, or as religious sites. Since items placed in caves are protected from the climate and scavenging animals, caves are an archaeological treasure house