from the 17th to early 19th centuries. It was declared a National Historic Landmark in 1967. The historic district was listed on the National Register of Historic Places in 1967 and it was relisted, with enlarged boundaries and expanded period of significance, in 1984. The historic district then covered of area and includes Amstel House and Old Courthouse which are separately listed on the NRHP. The area includes 461 contributing buildings, one other contributing structure, and one contributing object. The New Castle Court House, the Green, and the Sheriff's House are parts of First State National Historical Park, a unit of the National Park System. The national park interprets Delaware's settlement and role in the founding of the United States. Notable sites the historic district include: Amstel House, home of New Castle Historical Society Stonum, house of George Read Read House and Garden, former home of George Read Jr. The house, built between 1801 and 1804. Immanuel Episcopal Church on the Green New Castle Court House Museum, original colonial capitol; first state house of Delaware. Served as Court House until 1882, when county seat was moved to Wilmington. Its cupola served as the center of the Twelve-Mile Circle which defined Delaware's boundary with Pennsylvania. Old "Dutch" House, (ca. 1700), a typical small early dwelling Thomas McKean House New Castle Presbyterian Church, (1707) Lesley-Travers Mansion, built in 1855. The Bellanca Airfield, located outside of the Historic District, is the site of the former Bellanca Aircraft Corporation factory (1928–1960) which built over 3,000 airplanes. Delaware Aviation Hall of Fame Museum is located in hangar. Also nearby are Buena Vista, Glebe House, The Hermitage, New Castle Ice Piers, Penn Farm of the Trustees of the New Castle Common, and Swanwyck, all listed on the National Register of Historic Places. International relations The town attended a World Summit of towns called Newcastle held in Newcastle-under-Lyme in England for six days from 17 June 2006 Neuburg an der Donau, Germany Neuchâtel, Switzerland Neufchâteau, Vosges, France New Castle, Indiana, United States New Castle, Pennsylvania, United States Newcastle-under-Lyme, England Newcastle upon Tyne, England Newcastle, KwaZulu-Natal, South Africa Shinshiro, Japan Education New Castle is served by the Colonial School District. It operates William Penn High School. Private schools located in New Castle include: Serviam Girls Academy, St. Peter's Catholic School (of the Roman Catholic Diocese of Wilmington) and Delaware Valley Classical School. New Castle Public Library is the