Niagara Falls is a group of three waterfalls at the southern end of Niagara Gorge, between the Canadian province of Ontario and the US state of New York.

Located on the Niagara River, which drains Lake Erie into Lake Ontario, the combined falls have the highest flow rate of any waterfall in North America that has a vertical drop of more than 50 meters (160 ft). During peak daytime tourist hours, more than 168,000 m3 (six million cubic feet) of water goes over the crest of the falls every minute. Horseshoe Falls is the most powerful waterfall in North America, as measured by flow rate.

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