Marino de Alonisos

The National Marine Park of Alonnisos and the Northern Sporades was founded by presidential decree on 16 May 1992 and was the first of its kind in Greece. At some 2,260 km² it is the largest marine protected area in Europe. It comprises the island of Alonnisos and a constellation of uninhabited islands and islets around it, among them Peristera, Kyra Panagia, Gioura, Psathoura and Piperi.

Its founding purpose is the Mediterranean monk seal, one of the most threatened pinnipeds on the planet, of which only a few hundred animals remained worldwide. The sea caves of these islands, with inner beaches unreachable from land, are its main breeding area in the eastern Mediterranean. The island of Piperi is a zone of absolute protection: approaching closer than three nautical miles without scientific authorisation is prohibited.

The park also protects Posidonia meadows, rocky seabeds and a seabird community that includes Eleonora's falcon and Scopoli's shearwater, with important colonies on the islets. Underwater it preserves wrecks from antiquity, among them the one off Peristera, a fifth-century BC merchant ship laden with amphorae that opened to divers in 2020 as Greece's first underwater museum. The small-scale fishery of Alonnisos coexists with the protection through a zoning system, and management combines conservation with nature tourism.