At the entrance of the Gulf of Ajaccio, the archipelago of the Sanguinaires Islands, called Isuli Sanguinarri in Corsican, gathers 5 islands: the Mezu Mare Island also called Great Sanguinaire Island, the Cormorants Island also called the Isolotto, the island of the Cala d'Alga, the Porri Island and the boulder U Sbiru. This site is classified for the many endemic species that it shelters, but also for its historical monuments including the lighthouse evoked by the famous French writer Alphonse Daudet in one of the « Letters from My Windmill » (1869).