The world’s biggest cave passage


These are the breathtaking images which capture the hidden depths of the world’s biggest cave passage, which still has left cavers still searching for its end.Hidden in the depths of the Vietnamese jungle lies The Hang Son Doong, part of a network of over 150 caves.Discovered by British cavers in 2009, the cave passage in Phong Nha-Ke Bang National Park was originally thought to be a modest 150 metres long and 200 feet high.