The cave was formed between 2 and 5 million years ago. 
It is more than 200m high, 150m wide and approximately 5 to 6.5 km long. 
A jungle and a river inside the cave

Son Doong cave is big enough to contain a 40-storey skyscraper inside. It is classified as the largest in the world by the British Cave Research Association.

Urs Zihlmann said to Dailymail that he is very fortunate to be able to go on a guided tour of the cave.
'You feel very small as a human being in this enormous, underground paradise - it has such an unearthly beauty,” said the Aussie photographer.