One of the most important rivers in North America is the St. Lawrence River. It takes its source in the Great Lakes, leading to a vast estuary and the gulf of St.Lawrence to finally empty itself into the Atlantic Ocean. It is approximately 1,000 kilometers long. The river is the frontier between Canada and the USA for approximately 200 kilometers. In Canada, the navigation route runs along its entire length, forming the famous St. Lawrence Seaway that allows the Great Lakes to have an opening on the maritimes.
  Currently, many efforts are being made by the Federal Governement (Canada) to reduce the pollution within its waters and thus save from extinction some threatened species such as the so very precious Beluga (or white whale; sea mammel living in arctic waters).

Description borrowed from
Quebec Web
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