April 21, 2005—In a newly released photograph from the May National Geographic magazine, caver Alan Cressler, shown last August, rappels into Krubera Cave in the Caucasus Mountains of Russia—the world's deepest. Cressler was part of first phase of the Call of the Abyss project. The project's second expedition, in October, became the first to descend more than 2,000 meters (6,560 feet) underground.

Working underground for nearly four weeks, the August expedition involved 56 cavers, 45 men and 11 women, representing seven countries. They hauled in five tons of gear, rigging nearly 2 miles (3.2 kilometers) of rope and stringing a telephone wire to the bottom. Battling numerous vertical drops and freezing torrents of water—and blasting rubble from narrow passages—the August team reached a depth of 1,840 meters (6,037 feet).

In October a nine-person Call of the Abyss team entered Krubera. Using the ropes and anchors left by the August group, the 17-day expedition reached a depth of 2,080 meters (6,824 feet).

"Like climbing an inverted Everest," is how one caver described descending into Krubera. But "there is an important difference," said Alexander Klimchouk, the project organizer. "When you explore a cave, you don't know where the final limit lies—the terrain is not known in advance. And even now, we don't know whether we've reached the limit—or if it will go on. We're pretty sure we'll eventually go even lower."

—David Braun

The project was funded in part by the National Geographic Society. Alexander Klimchouk's account of the expeditions, a map, and more photos can be seen on National Geographic magazine's Web site.

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