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May 21, 2019 / 14:16

Son Doong is even bigger than we thought: CNN

Son Doong was inadvertently discovered by Vietnam resident Ho Khanh in 1990 and then became one of the world`s most precious natural wonders.

Kate Springer, editor from CNN - a US cable and satellite television news channel, has said Son Doong, the biggest cave in the world, appears to be even bigger than previously thought.
 
Son Doong Cave in Quang Binh province, Vietnam.
Son Doong Cave in Quang Binh province, Vietnam.
Last month, a trio of British divers -- the same ones who aided in the rescue of the soccer team trapped in cave in Thailand in 2018 -- ventured to Phong Nha-Ke Bang National Park, in the jungle-filled Quang Binh Province of central Vietnam, to explore the cave's waterways.
During the groundbreaking dive, they discovered a new underwater tunnel that connects Son Doong with another enormous cave called Hang Thung. Son Doong currently measures a total of 38.5 million cubic meters (about 1.35 billion cubic feet). When it's officially recognized as being connected with Thung Cave, it will add an additional 1.6 million cubic meters in volume.
"It would be like someone found a lump on top of Mount Everest, making it another 1,000 meters higher," says Howard Limbert, technical advisor of the Quang Binh-based Oxalis adventure tour company and one of the cave experts who helped organize the dive.
“Any cave in the world will be able to fit comfortably inside Song Dong when it's connected -- it's just outrageous in size,” He told CNN Travel.
Earlier, Oxalis, which is the only company licensed to bring travelers into Son Doong Cave, invited the British divers -- Jason Mallinson, Rick Stanton and Chris Jewell -- to visit the cave following the Thai rescue expedition.
"They wanted to do something interesting during the trip, so we came up with this idea of diving Son Doong, which had never been done before."
During the mission, divers were able to reach a depth of about 78 meters while diving on air (oxygen and nitrogen) before turning around.
"When the divers reached 78 meters, they plumbed the depth below using a line and a lead weight. Hence, they believe the offshoot reaches a depth of 120 meters and continues for about 1 kilometer," explains Limbert.
The team wasn't expecting the tunnels to be so deep, because the other caves in the area are quite shallow.
"Now that we know how deep it is, we'll bring the special gases [oxygen-helium mixture] with us next time to enable long, deep dives," adds Limbert.
The divers plan to return in April again next year. This is the best time of the year to dive, because water levels are relatively low, and visibility is better than usual -- though still only about one to two meters.
"I think it's incredible that something as important as the world's largest cave is still being explored and better understood," says Limbert.
"No one had ever set foot inside Son Doong until 2009 ... and this latest discovery shows there are still an awful lot of things to uncover on this planet. It's really exciting."