The Saint Lawrence River is located in North America, starting at Lake Ontario in Cape Vincent, N.Y., and Kingston, Ontario, and ending at the Gulf of Saint Lawrence, where it flows into the Atlantic Ocean. The Saint Lawrence River connects the Great Lakes with the Atlantic Ocean.
The Saint Lawrence River travels for a total length of 744 miles, with a maximum depth of about 250 feet. Only about 114 miles of the river flow through the state of New York, while the rest flow through the Canadian provinces of Ontario and Quebec. The Saint Lawrence River has a total basin area of about 520,000 square miles.