Structure of Son Doong Cave

The first expedition had been halted by an 80m high calcite barrier, which was jokingly dubbed the ‘Great Wall Of Vietnam’. It wasn’t until their second expedition in 2010, when the Great Wall was finally climbed and the end of the passage was found, that Hang Son Doong was determined to be the largest cave in the world.

At over 5km long, with sections reaching up to 200m tall and 150m wide, Hang Son Doong is large enough to house an entire New York City block, complete with 40 story skyscrapers. With a total measured volume of 38.5 million cubic metres, this comfortably surpasses Deer Cave in Malaysia, which was considered to be the previous record holder. Stalagmites up to 80m high have also been surveyed, the tallest ever encountered.