Niagara River

river that is the drainage outlet for the four upper Great Lakes (Superior, Michigan, Huron, and Erie), having an aggregate basin area of some 260,000 square miles. Flowing in a northerly direction from Lake Erie to Lake Ontario, a distance of about 35 miles, the Niagara constitutes part of the boundary between the United States and Canada, separating New Yorkstate from the province of Ontario. The relatively high, steady flow and steep gradient of the river combine to make it one of the best sources of hydroelectric power in North America. About halfway along the river’s course lies Niagara Falls, one of the major scenic spectacles of the continent. U.S. and Canadian cities of the same name stand on either bank of the river.