Lake Geneva or Lake Léman (French: Lac Léman, Léman, German: Genfersee) is a lake in Switzerland and France. It is one of the largest lakes in Western Europe. 59.53 % 345.31 km2 (133.32 sq mi) of it comes under the jurisdiction of Switzerland (cantons of Vaud, Geneva, and Valais), and 40.47 % 234.71 km2 (90.62 sq mi) under France (Haute-Savoie). The average surface elevation of 372 m (1,220 ft) above sea level is controlled by the Seujet Dam in Geneva.
The lake lies on the course of the Rhone. The river has its source at the Rhone Glacier near the Grimsel Pass to the east of the lake and flows down through the Canton of Valais, entering the lake between Villeneuve and Le Bouveret, before flowing slowly towards its egress at Geneva. Other tributaries are La Dranse, L'Aubonne, La Morges, La Venoge, and La Veveyse.