Vietnam’s Son Doong cave, Earth’s largest known cave passage, according to a survey team.
A massive cave recently uncovered in a remote Vietnamese jungle is the largest single cave passage yet found, a new survey shows.
At 262-by-262 feet (80-by-80 meters) in most places, the Son Doong cave beats out the previous world-record holder, Deer Cave in the Malaysian section of the island of Borneo.
Deer Cave is no less than 300-by-300 feet (91-by-91 meters), but it’s only about a mile (1.6 kilometers) long.
By contrast, explorers walked 2.8 miles (4.5 kilometers) into Son Doong, in Phong Nha-Ke Bang National Park, before being blocked by seasonal floodwaters—and they think that the passage is even longer.
Noisy and Intimidating
Son Doong had somehow escaped detection during previous British caving expeditions to the region, which is rich in limestone grottos.
“The terrain in that area of Vietnam is very difficult,” said expedition team member Spillane.
“The cave is very far out of the way. It’s totally covered in jungle, and you can’t see anything on Google Earth,” he added, referring to the free 3-D globe software.
(Related: “Google Earth, Satellite Maps Boost Armchair Archaeology.”)
“You’ve got to be very close to the cave to find it,” Spillane said. “Certainly, on previous expeditions, people have passed within a few hundred meters of the entrance without finding it.”
The team was told that local people had known of the cave but were too scared to delve inside.
“It has a very loud draft and you can hear the river from the cave entrance, so it is very noisy and intimidating,” Spillane said.
Bigger Caves Waiting?
Of more concern to the caving team were the poisonous centipedes that live in Son Doong.
The explorers also spotted monkeys entering through the roof of the cave to feed on snails, according to Spillane.
“There are a couple of skylights about 300 meters [985 feet] above,” he said. “The monkeys are obviously able to climb in and out.”
A biologist will accompany the team on its return visit next year to survey the cave’s subterranean wildlife.
Eavis, of the International Union of Speleology, added that there are almost certainly bigger cave passages awaiting discovery around the world.
“That’s the fantastic thing about caving,” he said.
Satellite images hint, for example, that caves even larger than Son Doong lie deep in the Amazon rain forest, he said.