Thanks to discoveries made during a recent expedition in Vietnam, it appears the world's largest cave, Son Doong, is even bigger than previously thought, CNN reported.
Last month, a trio of British divers -- the same divers who aided in the rescue of the trapped soccer team 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 (meaning "Mountain River Cave") 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 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.
He tells CNN Travel, "Any cave in the world will be able to fit comfortably inside Song Dong when it's connected -- it's just outrageous in size."
The dive included some members of the team that rescued the Thai soccer players from a cave where they were trapped for two weeks last year.
Son Doong is located in Central Vietnam, in the heart of the Phong Nha Ke Bang National Park. It is considered the largest cave in the world, based on volume. It was discovered by accident in 1990 and was only explored by the British Cave Research Association in 2009. It opened up to visitors in 2013 and is currently accessible only through the adventure tour company Oxalis.
The river cave is thought to be at least 3 million years old. It measures more than three miles long, and at its largest, the cave is more than 650 feet tall, and almost 500 feet wide.
The divers plan to return in April 2020. That month is considered the best for diving as it’s when the caves are easiest to explore because of low water levels and high visibility.
According Saigon Online, Phong Nha-Ke Bang National Park in the central province of Quang Binh, where the cave is located, is one of the most spectacular wilderness sites in South East Asia and one of the 2 largest limestone regions in the world.
It was recognized as a World Heritage site for the second time for its ecological system and biodiversity at the 39th session of the World Heritage Committee in Bonn, Germany in 2015. The first time was in 2003 for its geological and geomorphologic values.
It is home of more than magnificent 300 caves and ranks among the most popular tourist destinations in Vietnam, including the world's largest cave, Son Doong; the world's 3rd largest cave, En cave; and the longest dry cave in Asia, Thien Duong (Paradise) Cave.
