Lake St. Lawrence

Saint Lawrence Seaway
Specifications
Length	370 miles (600 km)
Maximum boat length	740 ft 0 in (225.6 m)
Maximum boat beam	78 ft 0 in (23.8 m)
Locks	15
Maximum height above sea level	570 ft (170 m)
Status	Open
History
Construction began	1954
Date of first use	April 25
Date completed	1959
Geography
Start point	Port Colborne, Ontario
End point	Montreal, Quebec

The Saint Lawrence Seaway (French: la Voie Maritime du Saint-Laurent) is a system of locks, canals and channels in Canada and the United States that permit ocean-going vessels to travel from the Atlantic Ocean to the Great Lakes of North America, as far inland as the western end of Lake Superior. The Seaway is named for the Saint Lawrence River, which flows from Lake Ontario to the Atlantic Ocean. Legally, the Seaway extends from Montreal, Quebec, to Lake Erie and includes the Welland Canal.

This section upstream of the Seaway is not a continuous canal; rather, it consists of several stretches of navigable channels within the river, a number of locks, and canals along the banks of the St. Lawrence River to bypass several rapids and dams. A number of the locks are managed by the St. Lawrence Seaway Management Corporation in Canada, and others in the United States by the Saint Lawrence Seaway Development Corporation; the two bodies together advertise the Seaway as part of "Highway H₂O". The section of the river from Montreal to the Atlantic is within Canadian jurisdiction and is regulated by the offices of Transport Canada in the Port of Quebec.

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