BLUEGROTTO
Blue Grotto
The Blue Grotto is a sea cave on the coast of the island of Capri, southern Italy. Sunlight, passing through an underwater cavity and shining through the seawater, creates a blue reflection that illuminates the cavern. The cave extends some 50 metres into the cliff at the surface, and is about 150 metres deep, with a sandy bottom.The above text is a snippet from Wikipedia: Blue Grotto (Capri)
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