Elmira (ĕlmĪˈrə) [key], city (1990 pop. 33,724), seat of Chemung co., extreme S central N.Y., on the Chemung River; settled 1788, inc. 1864. It is a distribution and manufacturing center with plants that make electronic and fire-fighting equipment, automobile parts, and iron and steel products. The Treaty of Painted Post, ending warfare between settlers and the Iroquois Confederacy, was signed there in 1791. The city was the site of a Civil War prison camp in 1864–5; 3,000 Confederate prisoners are buried there. The well-known Elmira Correctional Facility (est. 1876) led the way in prison reform. Mark Twain spent many summers in Elmira and is buried there. Places of interest include Twain's study, built in the shape of a riverboat pilot's house; the Arnot Art Museum; and a Native American historical museum. Elmira College and a business institute are in the city. Nearby are Harris Hill, site of an annual national glider contest, and Newtown Battlefield State Park, with a John Sullivan Monument.