New Castle

New Castle, city, New Castle county, northern Delaware, U.S. It is just south of Wilmington on the Delaware River, there linked to New Jersey by the twin spans of the Delaware Memorial Bridge. The original settlement, called Santhoeck, was established in 1651, when Peter Stuyvesant, the Dutch administrator, built Fort Casimir there. The settlement was seized by the Swedes in 1654 but was regained by the Dutch in 1655. It was named New Amstel and...