Niagara Falls, the most accessible and famous waterfall in the world, is actually three cataracts: the American Falls and Bridal Veil falls in New York and the Horsesshoe Falls in Ontario, Canada. More than 750,000 gallons of water flow each second in the summer.
For a good orientation to the falls, stop at the Niagara Visitor Center in the Niagara Reservation State Park (Prospect Park, Niagara Falls 14303), the oldest state park in the nation. Goat Island provides the closest view of the American Falls; cross to the Canadian side for the best view of Horseshoe Falls. The famous Maid of the Mist boat ride lets you view the falls from the water.
