What looked like a small hole in a cliff turned out to be the entrance to a massive borehole cave. In this video, we take you through the discovery, the first descent, and the jaw-dropping scale of ...

This turned out to be an INCREDIBLE adventure. It's rare to find such a variety of treasure in one location. This place was full of cool things to see and 30 million year old marine fossils.

Hells Canyon is the deepest river canyon in the United States. Now scientists have solved the mystery of when it formed.

The Xiaozhai Tiankeng stands as the textbook example of what happens when karst processes are given perfect working ...

The 'City of Caves', on an island in the Sea of Oman close to Mumbai, contains a collection of rock art linked to the cult of Shiva. Here, Indian art has found one of its most perfect expressions, ...