For cavers like the Limberts, discovering a cave as big as Son Doong is like finding a previously unknown Mount Everest underground. “We’ve just scratched the surface here,” Howard says of the national park, which was named a World Heritage site in 2003 for its forests and caves. “There is so much more to do.”
Anette Becher, a German caver and biologist, has found wood lice, fish, and millipedes inside the cave that are all white, which is common for creatures that live in the dark. And Dai Inh Vu, a botanist from the Vietnam Academy of Science and Technology, has identified the plants growing beneath the skylights, finding basically the same mix that grows in the forest above. But such science on the run is not the real focus of this expedition, whose central purpose is exploration.
Exploring Trip- By Mark Jenkins
When Howard and Deb first saw these enormous spaces, they felt certain they had discovered the largest cave in the world-and they might be right. There are longer caves than Hang Son Doong-the Mammoth Cave system in Kentucky, with 367 total miles, holds that record. There are deeper caves too-Krubera-Voronja, the “crow’s cave,” plunges 7,188 feet in the western Caucasus Mountains of Georgia. But for giant passages, there are few caves that can compare.
At the time of the Limberts’ discovery of Hang Son Doong, the largest passage was thought to be Deer Cave in Malaysian Borneo’s Gunung Mulu National Park, which was recently surveyed at 1.2 miles long, 500 feet wide, and 400 feet tall. But as the explorers would eventually determine, using precise laser instruments, Hang Son Doong is more than 2.5 miles long with a continuous passage as wide as 300 feet and, in places, over 600 feet high.
“We weren’t actually searching for the largest cave in the world,” Deb says. But she’s thrilled that the cave’s newfound fame might improve the lives of local villagers.
After five days of hiking, hauling, and crawling, the expedition is still only halfway into the cave. Counting all the cavers, scientists, a film and photography crew, and porters, we are a team of more than two dozen, which seems to have slowed us down. Besides that, the going gets dangerous as we climb through the breakdown in Watch Out for Dinosaurs: One misstep on slick boulders could mean a fall of more than a hundred feet.