1000 Wonders of the World!
Hang Son Doong
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Hang Son Doong

Wonder Type: Natural
Country: Vietnam
Best of: Cave
Hang Son Doong Cave 'cave of the mountain river' has the largest known cave passage cross-section in the world, and is located near the Laos-Vietnam border. Inside is a large, fast-flowing subterranean river. It was formed in Carboniferous/Permian limestone. Hang Son Doong was found by a local man named Ho Khanh in 1991. The whistling sound of wind and roar of a rushing stream in the cave heard through the entrance as well as the steep descent prevented the local people from entering the cave.
This article uses material from the Wikipedia article "Hang Son Doong", which is released under the Creative Commons Attribution-Share-Alike 3.0 License.