The Blue Grotto is a karst sea cave located on the northwestern side of the island of Capri, in the Metropolitan City of Naples. Once a prestigious Roman nymphaeum, the cave fell into decline and became widely known again in 1826, when it was visited by the German artist August Kopisch. The Blue Grotto has an entrance partially submerged by the sea, through which external light filters, creating the intense blue color that makes the cave so unique and famous. (source: Wikipedia)
