The Saint Lawrence Seaway

The St. Lawrence Seaway is a system of rivers, locks, canals and channels in Eastern Canada and the Northern United States that permits oceangoing vessels to travel from the Atlantic Ocean to the Great Lakes of North America, as far inland as Duluth, Minnesota, at the western end of Lake Superior. The seaway is named for the St. Lawrence River, which flows straight from Lake Ontario to the Atlantic Gulf of St. Lawrence. Legally, the seaway extends from Montreal, Quebec, to Lake Erie, and includes the Welland Canal. Ships from the Atlantic Ocean are able to reach ports in all five of the Great Lakes via the Great Lakes Waterway.