The Maddalena archipelago off Sardinia is a national park — pink granite islands, water so clear you can count the stones seven metres down. Sailors have been anchoring here for centuries, and the only thing that ruins it is engine noise. You will not hear any.

Taormina sits on a cliff above the Ionian with Mount Etna smoking behind it — you can swim in the morning and look at a live volcano with your aperitivo. Now imagine arriving at that view from the water, with your own boat waiting below the town.

Procida is the smallest inhabited island in the Bay of Naples — pastel houses, fishing boats, almost no cars. Locals say the best swim is on the far side, away from the ferry wake. That is where your captain will take you.

The Aeolian Islands are a UNESCO World Heritage site — seven volcanic islands, black sand beaches and hot springs you can swim in. Stromboli has been erupting almost continuously for thousands of years. Sailors call it the lighthouse of the Tyrrhenian.

Pozzuoli sits on the Phlegraean Fields, a volcanic caldera where the ground still breathes. Roman markets are half-submerged just offshore. You will anchor above a city older than most countries and swim in water heated from below.