City Island is a small island and a neighborhood approximately 1.5 miles (2.4 km) long by 0.5 miles (0.80 km) wide. At one time it was incorporated within the boundaries of Pelham, Westchester County, but it is now part of the New York City borough of the Bronx. As of the 2010 census the island had a population of 4,362. Its land area is 1.023 km² (0.395 sq mi, or 252.835 acres).