
Interior of a cave in north Alabama. Credit: Ky MacPherson
Not for the faint of heart, caving takes you underground among bats, through subterranean rivers, down mudslides, and into a world like none you’ve ever seen.
By Jayme Otto
It started with a 65-foot rappel down a ravine into the Rio Camuy. The river flowed a murky brown, colored by sediment, my guide said, “from the vibrant Puerto Rican forest.” I wasn’t exactly thrilled to submerge into water the color of chocolate milk, but this was the only way to access Resurgence Cave, part of the largest cave system on the island. My small expedition team dropped into the water, six people one-by-one, then flowed with the current toward the mouth of the 45-million–year-old cave. Although I knew what I’d signed up for, as I floated closer to the dark opening, a little voice in the back of my head whimpered, I’m going in there?
After swimming through the cave’s 20-foot entrance, I slithered up a mudslide to access its innards, flipped my headlamp on, and crawled on my stomach through a crack and into the first cavern. It took a moment to adjust to the darkness and get my bearings. The air was thinner, and I found it unsettling to know that my group wasn’t the only cluster of living things in the depths of this cave. Bats hung overhead, many-legged insects scrambled into the shadows, and an occasional guaba sighting caused me to gasp out loud. Harmless as they were, these gigantic arachnids resemble a spider straight out of Harry Potter.
Caving, called spelunking when it also involves underwater rivers, has been a pastime of adventurers and mystics for about as long as caves have existed. But only in the last century has this activity developed into a sporting endeavor. And just in recent decades, protective gear and equipment have made it appropriate for and accessible to folks who aren’t on death-wish expeditions.
My first caving expedition was little more than a hike, yet it involved improvisation to navigate alien terrain. I scrambled over large rock formations, crawled on knees and elbows, squeezed through cracks, slid down (and slithered up) mudslides, and glided through opaque brown water, all guided by a mere headlamp. The cave was completely dark, and even though Resurgence Cave has been mapped since 1973, I felt like I was going where no person had gone before. I couldn’t help but wonder what it must feel like to explore a virgin cave. Next time, perhaps.
Getting started:
- Caves are dark. Attach a headlamp to your helmet and bring at least two backup light systems (with new batteries) per person.
- Leave your GPS, your cell—and the route-finding string—at home. Maps are the best navigation tools for cave exploring.
- Caves hold a constant, cool temperature. Wear layers, mud-ready clothing, sturdy boots, and gloves to help maintain your body temp.
- Richard Rhinehart, author of Colorado Caves (Westcliffe Publishers, 2001), recommends tagging along with an experienced guide for your first underground expedition. He offers first-timers these additional nuggets of knowledge:
- Hang around caves long enough and you’ll see plenty of bats. But, an epidemic called white-nose syndrome is wiping them out. Learn more about preventing the spread of the epidemic here.
- Hands off! Your skin’s oils damage delicate mineral deposits formed into dripstone and flowstone (one of the most common cave formations, often found alongside stalagmites).
- Most caves are formed when seeping groundwater absorbs carbon dioxide that dissolves limestone and gypsum deposits below the surface. Water still percolates through “live” caves, caves in which formations are still growing, so expect slippery, muddy, wet surfaces.


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