The magnificent Hang Sơn Đoòng caves were discovered by a local farmer in 1991. It remained hidden from the locals all these years due to the lush forest and the slippery steep wall at the entrance of the cave. Only in 2009 did the cave become internationally known after a group of cave researchers conducted a survey.
This Hang Sơn Đoòng cave is the biggest in the world by volume, they are over 5km long and 200 meter high and 150 meter wide. The caves are punctuated by 2 large dolines, which is where the ceiling of the cave has collapsed and due to the entering sunlight this cross section of the caves is where the trees and other vegetation has grown. The Hang Sơn Đoòng caves have some of the tallest known stalagmites in the world, up to 70m tall, and behind a giant rock nick named ‘The Great Wall of Vietnam’ there are caves pearls the size of baseballs.
This spectacular cave of Hang Sơn Đoòng is not a trip for the faint-hearted to visit. It is a half day teak in the jungles through the knee deep rivers to reach the entrance of the caves. The tours are limited to only 450 visitors per year to maintain the caves eco-system; naturally these tickets sell out as soon they are released.