Grand Island is an island town in Erie County, New York, set in the Niagara River between Buffalo and Niagara Falls, with a population of 21,389 at the 2020 census. Its name comes from the French La Grande Île, and it is the largest island in the Niagara River. The town was organized in 1852 from part of Tonawanda, and paired bridges carrying Interstate 190 link it to the mainland at both ends. Beaver Island State Park lies at its southern tip and Buckhorn Island State Park at its northern end.