freshwater lake occupying a fault basin on the California-Nevada border in the northern Sierra Nevada, U.S. Fed by numerous small streams, it is drained by the Truckee River to Pyramid Lake, Nevada, about 60 miles (100 km) northeast. It measures 22 miles (35 km) north-south and 12 miles (19 km) east-west and has an area of 193 square miles (500 square km); its surface stands at 6,229 feet (1,899 m) above sea level, and its maximum depth is 1,640 feet (500 m). Visited in 1844 by the soldier-explorer John C. Frémont, the intensely blue lake took its name from the Washoe Indian word meaning “big water.” Water is supplied through its western outlet, the Truckee, for the Newlands Irrigation Project in Nevada. The lake and the surrounding area of national forests have been developed as tourist resorts.