The body of the unidentified hiker was found in a cave along the Appalachian Trail back in 1977.
This cave and others like it could one day provide the perfect place to build a lunar settlement.
Finland's Pirunkirkko cave is home to a unique phenomenon that makes it a popular place to contact spirits.
Scientists have suggested that subterranean lava tubes on Mars could be home to primitive alien life forms.
A small, unassuming cave in Venecia, Costa Rica has earned a reputation for proving almost immediately fatal.
For years, archaeologists have remained divided over the discovery of alleged giant skeletons and artifacts.
The disappearance of Kenny Veach still remains a topic of debate and intrigue almost 10 years on.
The bill requires that information about UFOs be disclosed, but now gives the Pentagon free reign to withhold whatever it wants.
Visitors to Pirunkirkko in Heinola, Finland have often felt the presence of some sort of spirit within the cave.
The swords were found in a high up, inaccessible crevice where they had been hidden two millennia ago.
The remarkable stunt was part of an experiment to help scientists better understand the effects of extreme isolation.
Hunter-gatherers who painted on cave walls 20,000 years ago also left behind something quite unexpected.
New research has suggested that the process of creating cave paintings may have been a family affair.
Police in Italy have discovered the remains of a man who is thought to have died over 50 years ago.
A caving team has become the first ever to descend into the depths of Yemen's terrifying sinkhole.
Caves dotted around the surface of the Red Planet could provide a safe haven for future human explorers.
A young girl buried in a European cave centuries ago was discovered with the head of a finch in her mouth.
Archaeologists have unearthed a child who was buried at Panga ya Saidi cave almost 80,000 years ago.
A gargantuan cave in the Canadian wilderness was only recently discovered because it had been filled with ice.
British railway workers have discovered a previously hidden cave that was exposed following a landslip.