Niagara Falls (/naɪˈæɡrə/ ny-AG-ra) is a city in Niagara County, New York, United States. As of the 2010 census, the city had a total population of 50,193, down from the 55,593 recorded in the 2000 census. It is adjacent to the Niagara River, across from the city of Niagara Falls, Ontario, and named after the famed Niagara Falls which they share.