These are the Most Beautiful and Mysterious Caves in the World
3 Blue Grotto
The Grotto Azzura is Capri’s most famous tourist attraction. It’s a half-flooded sea cavern that is filled with an eerie blue light. In the Roman period, the cavern was said to be the home of nereids, sirens, and devils, though some people still believe in this myth. The blue light is caused by sunlight filtering through an opening near the water’s surface. Anything immersed in the water also appears silver, due to bubbles in the water. The best time to visit the Blue Grotto is early afternoon, when the sunlight shines directly outside the cave.