Blue Grotto (Capri) Deep Dive
The Grotta Azzurra on the north coast of Capri is among the most visited and most photographed sea caves in the world. The chamber's electric blue light, produced by sunlight refracting through underwater openings, has drawn visitors since Roman antiquity.
Geology and optics
The cave is a partly-flooded sea cave cut by wave action into the Capri limestone. The visible entrance is a small one-metre opening above sea level; a much larger underwater opening admits sunlight that refracts through the water, illuminating the chamber from below with a saturated blue light.
Roman use
The cave was used by Emperor Tiberius (reigned AD 14-37) as a nymphaeum — a grotto sanctuary. Statues recovered from the cave floor confirm the imperial decoration; some are now in Capri's Certosa di San Giacomo museum.
Modern rediscovery
The cave was "rediscovered" in 1826 by Polish writer August Kopisch and Swiss painter Ernst Fries, with help from local fisherman Angelo Ferraro. Their accounts launched the cave's modern fame; Kopisch's "Discovery of the Blue Grotto" novella became famous in northern Europe.
The visit
Visitors transfer from larger boats to tiny rowboats outside the cave entrance, lie down to clear the one-metre opening, and enter the chamber lit by its blue glow. The whole experience inside lasts 5-10 minutes; oarsmen sing for tips. The chamber is closed in rough sea conditions, which can be most of the winter.
Crowds and conservation
Hundreds of visitors per day in peak summer queue for the brief access. The local rowboat consortium controls entry and charges per person on top of boat-trip fares. Many visitors report the experience as expensive relative to the brief time inside.
Practical
May-October most reliably; ride a boat from Marina Grande or Anacapri. Bring euros — credit cards not always accepted by the oarsmen.
Explore on the map
See the Blue Grotto on the interactive map.