The largest cave in the world is - Sơn Đoòng Cave Cave which is in Kungbin Province, Central Vietnam, 500 km. south of Hanoi. This "great" cave was discovered by chance a Vietnamese farmer named Ho Han. Walking through the National Park Phong Nha-Kẻ Bàng National Park, he heard the roar of a strong, whistling wind and suspicious noises coming closer, he found the entrance to the cave, but was afraid to go down, because it was a very steep descent.
In 2009, the cave explored British Speleological Association, but at the very beginning of his research group stumbled upon tyazhelopreodolimuyu barrier - 60 meter high wall of calcite, then the wall was called - "the great wall Vietnamese." Currently we studied 6500 meters of the cave, but presumably the total cave 38.5 million square meters.
