The Niagara River is about 35 mi (56 kilometres) long, including Niagara Falls.
Where the Niagara River makes a 90° turn, a Whirlpool has formed. The Whirlpool has a depth of 38 m or 120 ft. Like all whirlpools, the water circulates in a counterclockwise direction. There is an interesting phenomenon, that happens from about November 1 to April 1, after the water from the Niagara River is diverted before the Falls for the hydro electric power plants. The Whirlpool starts to move in a clockwise direction. This is because the water level is too low. During this time, the Niagara Whirlpool isn't technically a Whirlpool anymore, because that water is just flowing around the bend in the river in it‘s natural direction. . Above the Whirlpool, you can see the Spanish aero car. It was built an 1816 by Spanish engineers. It is the original car that is in operation today.
You can se the whirlpool on either of ouir Niagara Falls tours: Toronto to Niagara Tours, and Fall for Niagara
