Grotta delle Rondinelle

The Cave of Swallows is the signature dive of the Tremiti archipelago — a vast sea cave on San Domino island whose vaulted chambers glow with orange and yellow encrusting sponges, dense bouquets of yellow sea fans, and carpets of red gorgonians that start at 18 metres and deepen down the outer wall. The cave ceiling is encrusted with cup corals and the entrance walls host wall-to-wall invertebrate cover rarely seen elsewhere in the Adriatic; the cave's stillness makes it a nursery for juvenile fish of a dozen species.