river in eastern France and Switzerland, rising in the Savoy Alps and flowing north into the Rhône River below Geneva. Over its 62-mi (100-km) course, the river passes by some of the finest and most varied Alpine scenery. Its upper section collects the drainage of the northwest face of the Massif du Mont Blanc and is a source of hydroelectric power. Below Bonneville, in the Faucigny district, it flows through the Arve Valley, which is low-lying and highly cultivated.