Niagara Falls is the name of a trio of waterfalls (Horseshoe Falls, the American Falls and the Bridal Veil Falls) straddling the border of the United States and Canada in upstate New York and southern Ontario. The falls formed roughly 10,000 years ago during the Wisconsinan glaciation, the North American ice sheet complex’s most recent glacial period. More than 20 million people visit Niagara Falls every year. The best-known tourist attraction at the falls is the Maid of the Mist, named for an ancient Ongiara Indian mythical character. The boat has transported passengers into the rapids immediately below the falls since 1846.