Why is the Blue Grotto Blue?

Journey into an enchanting world of glowing blue waters, the Blue Grotto is by far one of the most famous natural attractions in southern Italy. A cave nestled in the coast of the island of Capri, simply hop on a rowboat and enter through the small hole in the jutting rocks. This cave is famous for its glow in the dark waters, enchanting tourists from all over. But how do these waters get their glow?

History of Blue Grotto

The Blue Grotto, once named as the Grotta di Gradola, has been known since the ancient Roman times. It was first used as Emperor Tiberius’ personal swimming hole. The cave was decorated by several statues, with built-in resting areas around the cave walls. The decoration dedicated to sea nymphs. The cave was then abandoned as legends stated spirits and demons inhabiting the waters. The cave was left uninhibited and unknown until the 1820s when the German writer August Kopisch and painter Ernst Fries were shown the grotto by a local fisherman.

Scientific reasons for why its blue

The reason for the blue glow is due to what lies under the water’s surface. There is a hole at the bottom of the cave, around about 9 metres wide, directly below the entrance to the Grotto. This hole filters sunlight from outside of the cave and combines with the entrance light to illuminate waters. The waters natural colour is already a pristine sapphire colour which gives the save its signature glow.

How to see it

You can only see the grotto by rowboat, as swimming is rescripted, and no other boats fit through the entrance. Either hop on an organised boat tour and travel out the coastline or hire a rowboat and skipper for the day. The best time to see this cave is when the sun is brightest, to see the most intense glowing effect. Noon until 2 pm is best, but usually means you will have to wait in line for up to an hour. The grotto tour itself only takes about 5-10 minutes but is well worth the wait.

The Blue Grotto is surely is something out of a dream. Put your hand in the water to see the bright, crystal blue waters make your hand glow. An exciting adventure that could only exist in a place this historic.

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