Saint Louis River (Lake Superior tributary)
Image source: USFWS Midwest Region
General data
- Name: Saint Louis River (Lake Superior tributary)
- Water system: St. Lawrence River
- Water type: River
- Progression: Lake Superior -> St. Marys River (Michigan–Ontario) -> Lake Huron -> St. Clair River -> Lake St. Clair (North America) -> Detroit River -> Lake Erie -> Niagara River -> Lake Ontario -> St. Lawrence River -> Gulf of St. Lawrence -> Atlantic Ocean -> Planet Earth
- Climates: Temperate
- Continents: North America
- Countries: United States of America
The Saint Louis River (abbreviated St. Louis River) is a river in the U.S. states of Minnesota and Wisconsin that flows into Lake Superior. The largest U.S. river to flow into the lake, it is 192 miles (309 km) in length and starts 13 miles (21 km) east of Hoyt Lakes, Minnesota. The river's watershed covers 3,634 square miles (9,410 km2). Near the Twin Ports of Duluth, Minnesota and Superior, Wisconsin, the river becomes a freshwater estuary.