The Guardian Blue Hole is said to have the second deepest cave in The Islands of The Bahamas, with a maximum explored depth of 436 feet (133 meters). The surface pond is fresh water, with a layer of hydrogen sulfide sometimes present at the halocline. The cave was named for a solitary barracuda that at one time inhabited the main entrance pond. Some of the walls of the cave are highly decorated with stalactites and stalagmites. Several deep pits within the cave drop from 45 m depths to more than 130 m.
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