YELLOWSTONE LAKE

lake in Yellowstone National Park, northwest Wyoming, U.S. It lies at 7,731 feet (2,356 m) above sea level and is the largest body of water in North America at so high an altitude. It is fed and drained by the Yellowstone River, which flows through the lake from south to north. About 20 miles (32 km) long and 14 miles (23 km) wide, the lake has a shoreline of 110 miles (177 km), a maximum depth of 390 feet (119 m), and a surface area of 137 square miles (354 square km). It is a haven for rare species of waterbirds, including trumpeter swans, and is prized for trout fishing.