Water flowing down the Niagara River and descending over the edge of 53-meter high Horseshoe Falls, one of the three falls that straddle the international border between the U.S. and Canada collectively known as Niagara Falls. The falls and river were created during the Wisconsin glaciation about 10,000 years ago by forces that also created the Great Lakes. The falls are a major tourist attraction today and a valuable source of hydroelectric power.