lake in Kootenai county, northwestern Idaho, U.S. It lies 25 miles (40 km) east of Spokane, Washington. Impounded by Coeur d'Alene Lake Dam on the Spokane River, it is fed by the Coeur d'Alene and St. Joe rivers. The lake is 30 miles (48 km) long and 1–3 miles (1.6–4.8 km) wide, with a 109-mile (175-km) shoreline. It is noted for its scenic mountainous beauty and is the centre of a resort area. Recreational facilities are widely available, and an amusement park is located nearby. The Kootenai County Fair is an annual event. Coeur d'Alene Indian Reservation borders the southern half of the lake. Coeur d'Alene city lies at the northern end of the lake and marks the western end of an area important for its forests and mineral deposits. The origin of the name, given by the French to Indians of the area, is uncertain.