The Horseshoe Falls, also known as the Canadian Falls, as most of it lies in Canada, is part of Niagara Falls, on the Niagara River. Approximately 90% of the Niagara River, after diversions for hydropower generation, flows over Horseshoe Falls. The remaining 10% flows over the American Falls. It is located between Terrapin Point on Goat Island in the US state of New York, and Table Rock on the Ontario side of the falls. According to official U.S. Geological Survey maps, approximately two-thirds of Horseshoe Falls is located in Ontario, Canada with the remaining one-third in New York, United States.
When the boundary line was determined in 1819 based on the Treaty of Ghent, the northeastern end of the Horseshoe Falls was in New York, United States, flowing around the Terrapin Rocks, which was once connected to Goat Island by a series of bridges. In 1955 the area between the rocks and Goat Island was filled in, creating Terrapin Point. In the early 1980s the United States Army Corps of Engineers filled in more land and built diversion dams and retaining walls to force the water away from Terrapin Point. Altogether 400 feet (120 m) of the Horseshoe Falls was eliminated. Constant erosion indicates the boundary line will alter into the future. Read more