A cave is a natural underground void large enough for an adult human to enter.
Some scientists stipulate that it must be large enough that some portion of it will not receive daylight; however, in popular usage, the term includes smaller spaces like cliff cavities, rock shelters and sea caves.
For more information about the topic Cave, read the full article at Wikipedia.org, or see the following related articles:
Recommend this page on Facebook, Twitter,
and Google +1:
Other bookmarking and sharing tools: