This archipelago is the largest nature reserve of marine birds in France. Boat trips leave from Trestraou and take visitors around the islands: first Rouzic, inhabited by an impressive colony of Northern gannets, then the Île de Malban and Île Bono, before reaching the Île aux Moines, where you can see the gun powder store, the lighthouse (with a panorama over the islands and the coast), then the fort - built by Vauban and now partly in ruins - and the old monastery below. On the way back there is a view of the Pointe de Ploumanach, the headland famous for its pink granite rocks.