Fort l'Écluse

Lock the Fort (or Fort of the Lock) is a fortified military structure built on a mountainside to control the march of Lock passage of the Rhone in western exit of the Geneva basin. This is a classified site that offers the remains of centuries of military architecture (towers, turrets watches, murderous, watchtowers, bunkers, ammunition rooms ...)

It is located in the town of Léaz, department of Ain, in a place called "The Longeray," one of the inputs of Regional Natural Park of Haut-Jura.