Rated as one of the world's top diving sites, Sipadan Island boasts a truly magical and breathtaking underwater experience. Situated at the heart of the Indo-Pacific Basin, the centre of the world's richest marine habitat, the oceanic island is surrounded by several exciting dive spots such as the Hanging Gardens, Barracuda Point and the Turtle Cavern. One of its most thrilling features (and certainly not for the faint-hearted) is the Drop Off, where knee-high water suddenly gives way to a 600m drop. 
 
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http://www.sipadan.com/