North of Aleria, the pond of Diane covers 570 hectares: it is the 3rd largest of the island and the deepest of the territory. Well known for its oyster production since ancient times, it even housed a Roman war port. Today, the lagoon is of great ecological interest because of its remarkable flora and fauna. Fish, amphibians, and mollusks benefit from trade with the sea and breed in numbers. Many species of rare birds come to nest in the luxuriant maquis that surrounds it. It is also exploited for fishing, shellfish farming, and aquaculture.