Extreme Gear: 7 Things You Need to Explore the World’s Deepest Caves

 Eliot Stahl

For their upcoming expedition into Sistema Huautla, the deepest cave in the Western Hemisphere, Bill Steele and Tommy Shifflett are bringing rope, and plenty of it – about 7,000 feet worth of static nylon made mostly by Pigeon Mountain Industries. In April, the two American explorers will lead a 26-person international team charged with proving that the 5,069-foot Sistema Huautla in Oaxaca, Mexico goes even deeper (and longer).

Exploratory caving requires highly specialized gear, most of which is hard to come by in the U.S. Steele uses Para Boots, made by Hi Tec, based in the Netherlands, which he buys on eBay. The boots are durable and waterproof, with Vibram rubber outsoles and a neoprene lining. Steele says they were originally designed for canyoneering, a popular activity in Europe. "They're just beautifully designed, and perfect for caving," he says. "I can walk right up a slick mud slope like it's easy."

For light, he uses a headlamp made by Switzerland-based Scurion, featuring state-of-the-art LED and Swiss engineering. "It's the best in the world," Steele says. "which matters for such a critical piece of equipment. The only light in a cave is that brought in by humans, so you need it to work, and work well."

Steele, like most cavers, carries up to three backup headlamps. His backups are made by Petzl, as is his helmet. He and team wear Cordura coveralls, which have only recently become available in the U.S. from outfitters like CaveSkinZ in Austin and Lost Creek in Indiana. Steele still prefers the European brand, Meander. He brings a wetsuit for long, deep canals that are wall-to-wall water and must be swum.

Both water and air in Huautla remain a consistent 60°F, a temperature that makes camping in the cave system comfortable, relatively speaking. Steele and team expect to set up at least one underground camp, maybe two depending on what they find down there. He says caving best-practice is to pack your sleeping bag in a Nalgene bottle to keep it dry.

"The thing to remember is that it's completely different underground," Steele says. "You walk though chest-high water, you climb through mud, it's dark, it's damp. Your gear has to be able to handle that."

Steele learned the hard way not to use leather boots, no matter how high-tech. "I destroyed a pair of $100 leather boots, back when $100 was something, in 18 days," he says. "I was climbing ropes that were right against the wall, so the boots were constantly wet, the leather was soft, and soon I had a flapper – which is what we call it when the toe of your sock starts coming out the front of your shoe.

Steele's top 3 picks for boots:

1. Hi Tec's Para Boots (The Netherlands)

2. Etche Securite's MIC Canyon Shoes (France)

3. Onguard's PVC Boots 6"H Lace-up (USA)