Búri cave
Búri is one of the biggest and most magnificent caves in Iceland, discovered by Björn Hróarsson in May 2005. The cave is massive and over one kilometer long. One of specific features of Búri lava tube is a 17 meters deep lava pit in the cave, which is said to be the deepest lava pit in the world. It is possible to reach the bottom of the pit using ropes and special equipment.
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