Great Lakes Waterway

The Great Lakes Waterway is a system of channels and canals that makes all of the Great Lakes accessible to oceangoing vessels. Its principal civil engineering components are the Welland Canal, bypassing Niagara Falls between Lake Ontario and Lake Erie, and the Soo Locks, bypassing the rapids of the St. Marys River between Lake Superior and Lake Huron, at Sault Sainte Marie. Maintained channels serve the St. Clair River and Detroit River between Lake Huron and Lake Erie. A United States Coast Guard icebreaker helps keep the passage open for much of the winter, although shipping usually ceases for 2 or 3 months each year.
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