The Niagara Falls are in the extreme south of the province of Ontario where the waters of Lake Erie plummet down almost 60 m (197 ft) into Lake Ontario below. Niagara Falls are amongst the largest, most beautiful and certainly most famous waterfalls in the world. They were first chronicled in 1678 by Jesuit missionary Louis Hennepin, who followed the sound of the rushing waters upstream along Lake Ontario to discover this great body of falling water, nowadays seen by over 12 million visitors a year.

The falls are in two parts, the concave Horseshoe Falls, 640 m (2100 ft) across, which are Canadian, and in the Province of Ontario, and the American Falls, about 330 m (1083 ft) across, in the State of New York, so the national boundary between Canada and the States runs through the middle.