The national forest of Eawy extends on an agricultural plateau between the Béthune and Varennes valleys. It consists of five parts: The Grand Massif de Saint-Saëns, the Basses Bréhoulles, the Croc, the Pimont, and the Naples. In 1204, it became a royal forest after the conquest of Normandy by Philippe Auguste. The Revolution later bound it to the State. Once rich in oak trees, the glass, construction, and marine industries decimated them in the 19th century and replaced them with beeches. Today, oaks, ashes, maples, hornbeams, cherry trees, and chestnuts are also present to ensure better biodiversity.