About a year ago I read Blind Descent: The Quest to Discover the Deepest Cave on Earth, by James M. Tabor. It tracks the efforts of two teams, one led by American Bill Stone to the Cheve Cave system in southern Mexico and the other, led by Ukrainian Alexander Klimchouk to the Kurbera supercave in the country Georgia.

Exploring caves is dangerous. It seems obvious, but Blind Descent opens it up in ways you wouldn’t imagine, from diseases to sound amplification (imagine sleeping next to a roaring 747 for months at a time) to The Rapture, an anxiety attack brought on by prolonged periods in darkness.

And by darkness, I mean complete darkness. Sometimes in spaces so tight you can barely wriggle through. All your light runs on batteries, and all your equipment must be protected.

You also have to deal with sumps, flooded underground tunnels which carry the risk of getting lost, damaging your equipment

And drowning:

Drowning is a cruel way to go. It throws two of the body’s most potent self-preservation reflexes into competition. Trapped underwater, you hold your breath as long as possible, with the urge to breathe growing from a whisper in your chest to a scream in your brain. As the carbon dioxide in your bloodstream builds up, you start to jerk and spasm. Gray fog closes down your peripheral vision. With your vision down to points of light, your fists clenched and toes curled as if in orgasm, your mouth opens not to scream but to inhale involuntarily. Finally, your lungs fill and you become negatively buoyant, floating slowly down, staring at eternity. There may be no good ways to die, but some are worse than others.

All in all, the book is great. Here’s a great interview with James Tabor about supercave exploration and be sure to check out this article about the Krubera Cave and the deepest point on earth, “Game Over”.