don their caving gear and descend into caverns like Lechuguilla and Mexico's Cueva de Villa Luz ("Cave of the Lighted House"). They go in search of bacteria that gobble up hydrogen sulfide gas and ...

Our expedition, however, had come prepared for a long siege, bringing more than five tons of gear to the cave. Ever since 1956, when explorers in France first descended below 1,000 meters (3,281 ...

If you have any gear with you, such as a sleeping bag or blanket, use it to enhance your comfort level. Before settling in, inspect the cave for potential hazards. Look for signs of rockfall or ...