Editing Great Lakes Waterway (section)

==Description==
[[File:Lower St. Marys shipping channels.jpg|thumb|The shipping channels pass on opposite sides of [[Neebish Island]] in the St Marys River]] 
The waterway allows passage from the Atlantic Ocean to the inland port of [[Duluth, Minnesota|Duluth]] on Lake Superior, a distance of {{convert|2,340|miles|km}} and to [[Chicago]], on Lake Michigan, at {{convert|2,250|miles|km}}.<ref>[http://www.boatnerd.com/facts-figures/cpgreat.htm The Great Lakes], [[boatnerd.com]]</ref> The elevation change from Lake Superior to sea level is {{convert|601|ft}}.

Together with the [[Saint Lawrence Seaway]], the Waterway accommodates both ocean-going vessels and ore, grain, and coal-bearing [[lake freighter]]s that travel from [[Gulf of St. Lawrence|the system's saltwater outlet]] to its [[Lake Superior|far interior]]. The Waterway has larger [[Lock (water transport)|locks]] and deeper [[Draft (hull)|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 [[Saint Lambert, Quebec]] 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. Major ports on the Great Lakes Waterway include [[Twin Ports|Duluth-Superior]], Chicago, Detroit, [[Toledo, Ohio|Toledo]], Cleveland, [[Two Harbors, Minnesota|Two Harbors]], [[Hamilton-Oshawa Port Authority|Hamilton]] and [[Thunder Bay Port Authority|Thunder Bay]].<ref>{{Cite web|title=Great Lakes {{!}} Names, Map, & Facts|url=https://www.britannica.com/place/Great-Lakes|access-date=2021-11-06|website=Encyclopedia Britannica|language=en}}</ref>

Shipping channels separate upbound traffic from downbound traffic. The upbound direction is away from the St. Lawrence River (westerly or northerly except in Lake Michigan where upbound is southerly). Channels are marked with navigation buoys in constricted areas and pilots are required on foreign boats. Recreational boats can use or cross the ship channels, but the large boats, with limited maneuverability, have right of way.