Deep inside the remote jungles of central Vietnam lies a hidden world so surreal that it feels like science fiction brought to life. Hang Sơn Đoòng is the world’s largest cave. It's a natural wonder ...

An excellent diving site, this incredible duo of caves is a favorite of both tourists and locals alike. The two caves—known as Cenote Dos Ojos—were created by two 70-foot sinkholes connected by a ...

The Hranicka Abyss is at least 1,325 feet deep, and likely goes down further. — -- A team of explorers believe they have discovered the deepest known underwater cavern the world in eastern Czech ...

(via MinuteEarth) Krubera Cave, one of our planet’s deepest known caves, extends 2200 meters into the earth – that’s a depth of nearly six Empire State Buildings. Or at least, that's as far down as ...

When Aidan Ward answered his phone from a clearing off the side of a road in southern New Mexico, he was exactly where he wanted to be: helping a geologist friend with cave research at Carlsbad ...