Song Dung Cave

Son Dung Cave in Vietnam is considered the largest cave in the world. Its width is about two hundred meters, the depth is about one hundred and fifty meters, and the length is almost nine kilometers, a whole city street with all the buildings on it can easily fit in the cave. Son Dung is twice the size of the Deer Cave in Malaysia, previously considered the largest known cave.

Son Dung was discovered in 1991 by a Vietnamese peasant named Ho Han, who feared the whistling sounds coming from the cave and called it the Mountain River Cave. Cave explorers explored the cave only in 2009. Son Dung was formed about two and a half million years ago when a river stream eroded the limestone rocks. In some halls of the cave, the ceiling collapsed, creating huge windows through which sunlight began to penetrate, and with it real jungles grew in the underground halls.

The cave is located on the territory of the Phongna Kebang National Park in the province of Quangbin near the border with Laos. The distance to the nearest town of Dongkhoy is sixty-five kilometers, ten of which you will have to walk. It will take you two or three days to explore the cave.