Great Lakes Circle Tour through the province, running the entire length from the Peace Bridge to the Ambassador Bridge. Unlike the other four Great Lakes, Lake Ontario is posted not as a circle tour but as part of the US-only Seaway Trail. The trail begins in Erie County, Pennsylvania and travels through Buffalo, Niagara Falls, Rochester, Oswego, and Ogdensburg before ending at the Seaway International Bridge near Massena. Plans for the Great Lakes Circle Tours were started in 1985. The Michigan Department of Transportation (MDOT) was in consultation with its counterparts in Wisconsin (WisDOT), Minnesota (MnDOT) and Ontario (Ministry of Transportation of Ontario, MTO)
Great Lakes Waterway lake freighters to travel from the system's saltwater outlet to its far interior. The Waterway has larger locks and deeper drafts than the lower Seaway, limiting large freighters to the four lakes upstream of the Welland Canal and Lake Ontario and similarly restricting passage beyond the canal by larger ocean vessels. The two waterways are often jointly and simply referred to as the "St. Lawrence Seaway", since the Great Lakes, together with the St. Lawrence River, comprise a single navigable body of freshwater linking the Atlantic Ocean to the continental interior. Shipping channels separate upbound traffic from downbound traffic. The