Pozzuoli / Baiae

Naples Bay cradles one of the ancient world's most extraordinary dive sites — the submerged Roman city of Baiae, whose thermal-volcanic subsidience carried imperial villas, mosaic floors, and marble statues beneath 3 to 15 metres of clear Tyrrhenian water. Divers and even snorkellers glide above intact column capitals and Emperor Claudius's nymphaeum, while the surrounding volcanic seabed harbours surprisingly rich Mediterranean marine life.