The falls are divided into two parts by Goat Island. The larger portion, on the southwest side, is the Canadian falls, known as the Horseshoe Falls. It measures 2,600 feet (790 meters) along its curve and drops 162 feet (49.4 meters). The smaller American falls is northeast of Goat Island. It is 1,000 feet (305 meters) across and drops about 167 feet (51 meters). Between the American falls and Goat Island are the small Luna Island and the small Luna, or Bridal Veil, Falls.
Both the United States and Canadian governments have built parks, viewing platforms, paths, and highways. The Niagara Reservation State Park was established in 1885 and is New York's oldest state park. It includes an observation tower, elevators that descend into the gorge at the base of the American falls, and boat trips into the waters at the base of the Horseshoe Falls.
Putting Niagara Falls to Work
The control of Niagara Falls between the United States and Canada has long offered the world an example of international cooperation. A treaty in 1910 and later agreements fixed the amounts of water that could be diverted. An international Niagara Control Board was established in 1923.
Between 1954 and 1958 the United States and Canada completed the Niagara Remedial Works Project. This enormous operation checked erosion with a gated control structure, excavations, and fills.
The Hydro-Electric Power Commission of Ontario completed the Sir Adam Beck-Niagara Generating Station No. 1 in 1925 and No. 2 in 1958. The combined capacity of the plants is 1,443,000 kilowatts.
In 1957 the United States Congress approved the construction of the Niagara Power Project by the Power Authority of the State of New York. It has a capacity of 2,190,000 kilowatts. The first electric current from the project was delivered in 1961.
How Niagara Came to Be
The falls of Niagara are about 25,000 years old. The hard rock (Lockport dolomite) at the brink of the falls is much older. It was made on the bed of an inland sea in the Silurian period, between 395 million and 430 million years ago. Gradually the limy sediment hardened to stone—either limestone or dolomite, a limestone with magnesium.
Many ages later, glaciers covered the Niagara region (see Ice Age). As the last glacier retreated, it left Lake Erie at its southern edge. Water from the lake began to spill over the Niagara escarpment into the Ontario basin below, just south of where Queenston and Lewiston now stand.
Niagara's rate of cutting has changed many times. It started slowly, for at first the river drained Lake Erie only. Lakes Superior, Michigan, and Huron had a northerly outlet. The drainage changed as glaciers retreated. Water from all four lakes then poured over the falls. When the river spread to the point where the famous whirlpool now is, it reached an ancient valley that had cut into the dolomite from the west. Later the valley filled with glacial debris. The river wore away the soft material, forming the 60-acre (24- hectare) basin. The Rev. Louis Hennepin, a priest who accompanied the explorer La Salle, was the first European to view the falls of the Niagara River, in 1678. The site was of strategic use to the British and French in the struggle to control the Great Lakes. The British built Fort Schlosser there in 1761.