Hang Son Doong (Mountain River Cave) in Vietnam

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An evening pause: As I have been out today doing survey work for a cave project of which I am the cartographer, I thought this video of Hang Son Doong (Mountain River Cave) would be appropriate.

Note that this cave is definitely not the largest in the world, as is often claimed. It appears to have the largest single room of any known cave, but the cave itself is relatively small at about four miles, compared for example to Mammoth Cave in Kentucky, which is the world’s longest cave at 400 miles.



  • danae

    Would it be largest based on the volume of space inside? It certainly dwarfs its visitors. The photos are breathtaking.

  • It is a breathtaking cave, but in terms of volume it doesn’t even come close to Mammoth, or other large systems that top a hundred miles. See the long cave list for the world and the U.S. long cave list.

  • Dave Hollick

    I’m surprised by how many caves on this list I’ve been in, and even more surprised by how many I’ve never heard of. Also, should caves that are entirely under water be included, or be on a separate list?

  • danae

    Yes, I see now that Mammoth is the colossus of caves, no contest.

    I’m shocked to find that I live about 3 hours from the 11th deepest cave in the U.S. A very cold, wet one, but apparently very nicely decorated. A relative once walked to its entrance during a much longer back-packing excursion in the Seven Devils, but I’ve never heard anyone else even mention its existence.

    Really, you have the most interesting avocation.

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