photos by john spies of the the sơn doòng cave in vietnam. at 200 metres high, 150 metres wide and five kilometres long, it is the biggest cave in the world — so large, it has its own river, jungle and even climate. it also contains the world’s tallest stalagmite, which stands over 80 metres tall (third photo). (stalagmites are formed one drop of water at a time, with minerals in the water building up over time)
despite its immense underground size, the cave is practically invisible from the outside, seen only from the mist wafting from surface cracks. with a huge temperature difference between the cooler air inside the cave and warmer outside air, son doong is home to moving clouds of mist which, when illuminated by natural light as far as four kilometres away, create the surreal atmosphere seen in the photos.
(see also: previous cave posts)