Venturing alone into the depths of a remote cave is already a challenge—but what he found inside made this journey even more ...

With high carbon dioxide, low oxygen and no photosynthesis, here’s how an entire ecosystem persists in Movile Cave, one of the most extreme environments on Earth.

Deep under the Chihuahuan Desert is a natural wonder, a cave filled with beautiful giant crystals, but which also happens to be a potential death trap.