Inside world of Son Doong cave

These breathtaking images capture the hidden depths of the world’s biggest cave passage – so large the end is yet to be found. Hidden in the depths of the Vietnamese jungle lies The Hang Son Doong, part of a network of over 150 caves.

Inside world of Son Doong caveSurrounded by jungle and used in the Vietnam war as a hideout from American bombardments, the cave passage is so large that it could hold a block of 40-storey skyscrapers. Its entrance was only rediscovered by British cavers in 2009.

To enter the cave, explorers had to use ropes to drop down 80m depth to begin the journey to explore the world in Son Doong cave.

Four years after the cave was revealed to the world, the tour to conquer Son Doong cave was tested in August, opening up the opportunity to explore the cave for tourists. The test will continue in February and March 2014. Each group of tourists will have up to six people, with the cost of $3,000. More than 100 international visitors have registered for the tours in 2014.