A dune cordon separates Utah Beach from the marshes of the back coast in the Manche department. It forms an aerodynamic accumulation of sand essential for damping the wind and marine energies and protects the back-coast against storms and the flooding of low-lying coastal areas. Measures such as the installation of windbreak curtains, the planting of vegetation, the covering with branches, the reprofiling and the recharging of the dune, as well as the channeling of the touristic frequentation, allow its natural evolution and the control of its mobility.