The St. Lawrence Seaway—completed the same year as this map of the project, 1959—is jointly managed by Canada and the U.S. It is a series of canals and locks that opens the Great Lakes to ocean-going vessels.
Map by U.S. Navy

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    On June 26, 1959, the St. Lawrence Seaway officially opened with a ceremony in St. Lambert, Quebec, Canada, attended by Queen Elizabeth II and U.S. President Dwight D. Eisenhower. The St. Lawrence Seaway opened the Great Lakes to ocean-going traffic.
    The St. Lawrence Seaway, named for the river that flows from Lake Ontario to the Atlantic Ocean, was a joint U.S.-Canadian effort. It stretches nearly 4,025 kilometers (2,500 miles), from the Atlantic Ocean to the port of Duluth, Minnesota, on the western shore of Lake Superior. The seaway is not a single unified route, but a series of canals, locks, and dredged waterways. 
    More than 40 million tons of cargo pass through the St. Lawrence Seaway every year. About half of that traffic is from international sources, mostly Europe and the Middle East. The other half is trade between U.S. and Canadian ports.
  • Term Part of Speech Definition Encyclopedic Entry
    canal Noun

    artificial waterway.

    cargo Noun

    goods carried by a ship, plane, or other vehicle.

    ceremony Noun

    activities to celebrate or commemorate an event.

    dredge Verb

    to remove sand, silt, or other material from the bottom of a body of water.

    Great Lakes Noun

    largest freshwater bodies in the world, located in the United States and Canada. Lake Huron, Lake Ontario, Lake Michigan, Lake Erie, and Lake Superior make up the Great Lakes.

    lock Noun

    structure on a waterway where gates at each end allow the water level to raise and lower as they are opened and closed.

    port Noun

    place on a body of water where ships can tie up or dock and load and unload cargo.

    Encyclopedic Entry: port
    route Noun

    path or way.

    shore Noun


    trade Noun

    buying, selling, or exchanging of goods and services.

    traffic Noun

    movement of many things, often vehicles, in a specific area.