LÉAZ: GENEVA - SURROUNDINGS: Fort l'Écluse, 'Fort de l'Ecluse près Genève', Lithography v. Du Bois, around 1800, 8.5 x 11.5 Fort l'Écluse or Fort de l'Écluse is a military fort in Léaz, Ain, near Collonges in eastern France. It dominates the Rhone Valley as a natural entrance to France from Switzerland between the Vuache and the Jura (qt. n. Wikip.). - With narrow margins, clean and in good condition. Item number: 333244.