Deep inside a labyrinthine cave in southwestern France, ancient humans who lived around 30,000 years ago carved horses, ...

Veteran cavers Peter and Ann Bosted were cruising around their hometown of Hawaiian Ocean View ... cave that the Kanohina system seems poised to supplant in the record books is on the other side ...

Walking into Fingal's Cave is like walking into the heart of the Earth. Here among the towering basalt columns, the visitor stands inside a lava ... to see the raw side of nature as inspiring.

Take an otherworldly journey through Hang Son Doong, the world's largest cave located in Vietnam. The cave is more than 500 feet tall, 650 feet wide, and 29,500 feet long. Video courtesy of Ryan ...