Niagara Falls is a group of three waterfalls –the Horseshoe Falls, the American Falls and the Bridal Veil Falls– located in the international border between Canada and the United States. They are situated specifically between the province of Ontario and the state of New York. They form the southern end of the Niagara Gorge.
The Horseshoe Falls, the largest of them, lie mostly on the Canadian side and the American Falls entirely on the American side, separated by Goat Island. The smaller Bridal Veil Falls are also located on the American side, separated from the other waterfalls by Luna Island.
The three of them are located on the Niagara River, 27 km north-northwest of Buffalo, New York and 121 km south-southeast of Toronto, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York. The international boundary line was originally drawn through Horseshoe Falls in 1819, but the boundary has long been in dispute due to natural erosion and construction.
While not exceptionally high, the Niagara Falls are very wide. Altogether, the three of them form the highest flow rate of any waterfall in the world, with a vertical drop of more than 50 metres. Horseshoe Falls alone is the most powerful waterfall in North America, as measured by vertical height and also by flow rate.
Niagara Falls were formed when glaciers receded at the end of the Wisconsin glaciations, which was the last ice age. In that time, water from the newly formed Great Lakes carved a path through the Niagara Escarpment in their way to the Atlantic Ocean.
The Niagara Falls are renowned both for their beauty and as a valuable source of hydroelectric power. Managing the balance between recreational, commercial, and industrial uses has been a challenge for the stewards of the falls since the 19th century.