The Saint John River is a river, approximately long, located principally in the Canadian province of New Brunswick but also in and arising from the province of Quebec and the U.S. state of Maine. It forms part of the Canada–United States border in two different places along its length. The river drains an area of approximately , of which slightly more than half is located in New Brunswick. Along that portion of the Atlantic shoreline of North America that lies between the St. Lawrence River and the Mississippi River, the Saint John River is the second longest waterway; only the Susquehanna is longer. It has been nicknamed the "Rhine of North America". The river is regulated by hydro power dams located at Mactaquac, Beechwood, and Grand Falls, New Brunswick.