A cave is "a natural opening in the ground extending beyond the zone of light and large enough to permit the entry of man," according to the U.S. Geological Survey. Caves can range in size from single rooms to large formations with winding passageways that extend for miles. Caves typically form in types of rock, such as limestone, that dissolve in water. It can take tens of thousands to hundreds of thousands of years for caves to form. The study of caves is called speleology, and the exploration of caves is called spelunking. Caves are famous of their dripstone features called speleothems, the most well-known of which are stalactites and stalagmites. Many of the strange creatures found in caves have adapted to live in near or total darkness — some are blind to visible light. See cave pictures and read about the latest cave discoveries and speleological research below.
Latest about caves
Ancient cave burial of 'Jesus' midwife' may actually hold a princess
The site's architecture may indicate the Judaean princess was buried there.
'Trash' found deep inside a Mexican cave turns out to be 500-year-old artifacts from a little-known culture
When two spelunkers investigated what they thought was trash in a cave in Mexico, they discovered more than a dozen artifacts dating back centuries.
Neanderthals, modern humans and a mysterious human lineage mingled in caves in ancient Israel, study finds
A newly excavated cave in Israel holds burials and artifacts suggesting that multiple human species commingled and shared ideas there during the Paleolithic.
Golden scaleless cave fish discovered in China shows evolution in action
The discovery of a golden scaleless fish in China is helping scientists understand how animals evolved to live in caves.
7 haunting caves ancient humans used for art, burials and butchering
From stunning artwork to evidence of elaborate prehistoric butchering, Live Science takes a look at seven amazing caves that contain archaeological remains.
35,000-year-old 'tortoise shell' carving may be Holy Land's oldest evidence of ritual behavior
A carved boulder found deep in a cave in Israel may have been used for rituals more than 35,000 years ago.
Marble Caves: Chile's ethereal turquoise caverns with 'mineral ice cream' on the walls
The Marble Caves sit on the shores of a turquoise glacial lake in southern Chile. Light bounces off the water onto the walls, creating a magical, ever-changing display inside the caverns.
Hang Son Doong: The world's biggest cave, so 'outrageous in size' it fits 2 jungles and the 'Great Wall of Vietnam'
Vietnam's Son Doong cave is so large, you could squeeze 15 Great Pyramids of Giza inside it and fly a Boeing 747 airplane through some of its passages.
