Grand Island is a town and an island in Erie County, New York, USA. As of the 2000 census, the town population was 18,621. The current town name derives from the French name "La Grande Ile," as Grand Island is the largest island in the Niagara River. The phrase "La Grande Ile" appears on the town seal. The Town of Grand Island is located at the northwestern corner of the county. The town is northwest of Buffalo, New York. Interstate 190 and New York State Route 324 cross the island.