The cliffs of Bessin in the Calvados department are divided into several homogeneous sections depending on the nature of the rock that constitutes the foot of the cliff. At the place called La Falaise in Arromanches-les-Bains, the cliff is thus composed of about half of a limestone cornice and, for the other half, of a marly base less resistant to maritime erosion. From Arromanches to Saint-Côme-de-Fresne, limestone marls from the Lower Bathonian form the foot of the cliff and are overhung by a thinner limestone cornice, only 16.4 to 19.6 ft (5 to 6 m) thick.