![]() Son Doong Cave, was made public in 2009 by a group of British scientists from the British Cave Research Association after they extensively surveyed the area. Photo:Carsten Peter / National Geographic Creative ![]() Located approximately 500km south of Hanoi, Son Dong cave is more than 200m wide, 150m high and about 9km long. It houses a jungle and a river and could fit a 40-storey skyscraper within its walls. Photo:meteoweb.eu ![]() ![]() “The Troll’s Tongue” in Hordaland, Norway Photo:J Wildman / Getty Images ![]() ![]() ![]() ![]() ![]() ![]() ![]() Neptune Islands, Australia Photo:Michael Melford, National Geographic ![]() The blood-red Lake Tuz in Aksaray, Turkey Photo:Anadolu Agency / Getty Images ![]() “Death Road” in the Yungas region of Bolivia Photo:Nick Smith / Guzelilian ![]() Mount Hua Shan in in Huayin, China Photo:Flocu / Getty Images ![]() Ellison’s Cave in Georgia, United States Photo:Michael Nichols / National Geographic ![]() |
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