San Pietro Island

San Pietro is a volcanic island off the Sulcis coast, half an hour by ferry from Portovesme or Calasetta. Carloforte, its only town, still speaks the Tabarchino of its Ligurian settlers: an identity you find in the alleys and in the cooking — tuna above all.

For snorkelling the best sides are the south and west: at the Colonne, the trachyte stacks off La Bobba beach, you swim among boulders and crevices full of sea breams, octopuses and parrotfish — a species now at home in the Sulcis. La Caletta (Spalmatore) is the most convenient, sheltered bay for getting in from shore.

The west coast, from Capo Sandalo to the Mezzaluna coves, is high, exposed and nearly uninhabited: explore it on a round-the-island boat trip, alternating caves and swim stops. Eleonora’s falcons nest on the cliffs, and in calm seas the water beneath the walls is a deep, immaculate blue.