* The length of the Niagara Gorge? This is the canyon carved by the Niagara River, stretching from the falls to Lake Ontario. It is approximately 35 kilometers (22 miles) long.

* The length of the Horseshoe Falls (also known as the Canadian Falls)? This is the largest of the three waterfalls at Niagara Falls. It's about 1,676 feet (511 meters) wide at the top.

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