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Near the island of Mauritius, there appears to be a giant underwater waterfall flowing into the ocean. In reality, it is an optical illusion created by sand and silt being pulled down underwater slopes by strong ocean currents. From above, the movement of the sediments looks remarkably like water pouring over the edge of a cliff. Although it isn't a true waterfall, the effect is so convincing that it has become one of the world's most famous natural illusions.
It is also a popular destination for aerial photography and sightseeing.
© National Oceanic and Atmospheric Administration