Great Lakes Waterway River between Huron and Erie. Usually, one or more U.S. Coast Guard icebreakers help keep the water passage open for part of the fall and early winter, although shipping usually ceases for two to three months thereafter. The Great Lakes Waterway is co-administered by the governments of Canada and the United States of America. The waterway allows passage from the Atlantic Ocean to the inland port of Duluth on Lake Superior, a distance of and to Chicago, on Lake Michigan, at . Together with the Saint Lawrence Seaway, the Waterway allows both ocean-going vessels and the ore, grain and coal-bearing
Duluth, Minnesota is credited with the European discovery of Lake Superior before 1620. Pierre-Esprit Radisson and Médard des Groseilliers explored the Duluth area, Fond du Lac (Bottom of the Lake) in 1654 and again in 1660. The French soon established fur posts near Duluth and in the far north where Grand Portage became a major trading center. The French explorer Daniel Greysolon, Sieur du Lhut, whose name is sometimes anglicized as "DuLuth", explored the Saint Louis River in 1679. After 1792 and the independence of the United States, the North West Company established several posts on Minnesota rivers and lakes, and in