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9 jaw-dropping caves

By: Catie Leary on June 11, 2010, 1:05 p.m.
Blue Grotto

Photo: ZUMA Press

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Blue Grotto

This famous sea cave is located off the coast of the island of Capri, Italy. It is notable for its gorgeous and brilliantly blue waters, a color created by sunlight shining through the seawater into the underwater passageway. During the times of the Romans, the cave was thought to be the home of witches and monsters, but that doesn't deter visitors today — it remains one of the most popular attractions on the island of Capri.