The Croton Aqueduct or Old Croton Aqueduct was a large and complex water distribution system constructed for New York City between 1837 and 1842. It was one of the first great modern aqueducts and transported water by the force of gravity alone 41 miles (66 km) from the Croton River in Westchester County into reservoirs in Manhattan, where local water resources had become polluted and inadequate for the growing population of the city. Although the aqueduct was supplemented and largely superseded by the New Croton Aqueduct, which was built in 1890, the Old Croton Aqueduct remained in service until 1955.