The formation of the Niagara gorge (downriver) and the maintenance of the falls as a cataract depend upon peculiar geologic conditions. The rock strata from the Silurian Period (about 445 to 415 million years ago) in the Niagara gorge are nearly horizontal, dipping southward only about 20 feet per mile (almost 4 metres per km). An upper layer of hard dolomite is underlain by softer layers of shale. Water exerts hydrostatic pressure and only slowly dissolves the dolomite after infiltrating its joints. Dolomite blocks fall away as water from above infiltrates and rapidly erodes the shale at the falls itself. The disposition of the rock strata provides the conditions for keeping the water constantly falling vertically from an overhanging ledge during a long period of recession (movement upstream) of the cataract. As blocks of dolomite are undercut they fall off and are rapidly destroyed by the falling water, further facilitating the retreat of the falls and the maintenance of a vertical cataract.
The water flowing over the falls is free of sediment, and its clearness contributes to the beauty of the cataract. In recognition of the importance of the waterfall as a great natural spectacle, the province of Ontario and the state of New York retained or acquired title to the adjacent lands and converted them into public parks.

In recent years the very large diversion of water above the falls for hydroelectric-power purposes has lessened the rate of erosion. Elaborate control works upstream from the falls have
maintained an even distribution of flow across both the U.S. and Canadian cataracts, thereby preserving the curtains of the waterfalls. A large part of the great river above the falls is diverted and disappears into four great tunnels for use in the power plants downstream. Owing to concern over the possibility of major rockfalls, water was diverted from the American Falls in 1969, and some cementing of the bedrock was done; an extensive boring and sampling program was also carried out. River flow was returned to the American Falls in November of that year, and it was decided that safety measures for the viewing public should be implemented and that measures to stem natural processes were both too expensive and undesirable.

Excellent views of the falls are obtained from Queen Victoria Park on the Canadian side; from Prospect Point of the U.S. side at the edge of the American Falls; and from Rainbow Bridge, which spans the Niagara gorge about 1,000 feet (300 metres) downstream from Prospect Point. Visitors may cross from the U.S. shore to Goat Island by footbridge and may take an elevator to the foot of the falls and visit the Cave of the Winds behind the curtain of falling water. The Horseshoe Falls, which carry about 90 percent of the river’s discharge, receded upstream at an average rate of about 5.5 feet (1.7 metres) per year in 1842–1905. Thereafter, control works and the diversion of water decreased the erosion rate, which is presently so slow at the American Falls that large blocks of dolomite accumulate at the base of the falls, threatening to turn it into rapids.

Location
The Niagara falls is located 17 miles (27 km) north-northwest of Buffalo, New York, 75 miles (120 km) south-southeast of Toronto, Ontario, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York.

Historical Importance
In 1604, Frenchman Samuel de Champlain visited the area during his exploration of Canada. In 1677, the Belgian Father Louis Hennepin, observed and described the Falls after traveling with explorer René Robert Cavelier and Sieur de la Salle. In early 1700s, the Finnish-Swedish naturalist Pehr Kalm, explored the area and wrote his experience. Credible evidence says that French Jesuit Reverend Paul Ragueneau visited the falls some 35 years prior to Hennepin's visit.

Nearby Attractions
Niagara Fallsview Casino Resort
It is a 2.5 million square foot complex that includes more than 3,000 slot machines and 150 gaming tables, a 368-room five-star hotel, fine-dining restaurants, 50,000 square feet of meeting/conference space, a health spa, a retail facility, and a 1,500-seat theatre.

Skylon Tower
It offers a spectacular view 775 feet (236 meters) above Niagara Falls from its Observation Deck.

MAX Theatre Niagara Falls
It offers the thunderous power of Niagara Falls from a heart-thumping perspective. The IMAX Theatre Niagara Falls features more than six-story high screen and 12,000 watts of floor shaking digital surround sound.

Marineland
Marineland features park rides and marine shows that include beluga whales, killer whales, dolphins and other wildlife, such as deer and bears.

Butterfly Conservatory / Botanical Gardens
The Butterfly Conservatory is part of the Niagara Parks Botanical Gardens close to Niagara Falls. It has an indoor, climate-controlled facility that features a network of paths in a tropical rainforest setting where thousands of butterflies breed.

How to reach
By Air - Niagara Falls can be reached by Air and the nearest airports are Buffalo Niagara International Airport in Cheektowaga, New York.
Toronto Pearson International Airport in Mississauga, Ontario. Hamilton/John C. Munro International Airport in Mount Hope, Ontario. By Rail - Amtrak Station - Toronto and New York City
By Road - Bus facilities are available from Greyhound Canada to Toronto and Buffalo and also from Coach Canada to Toronto and Buffalo.


There are taxis available from Buffalo, New York to Niagara Falls, Ontario and Toronto.

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