The Historic House Trust of New York City was formed in 1989 as a public-private partnership with the New York City Department of Parks and Recreation to preserve the historic houses located within New York City parks, although most of the houses were not originally city-owned. The Trust works with the individual houses to restore and promote the houses as a means of educating residents and visitors about the social, economic and political history of New York City and cast urban history in a new light. The Trust includes 23 historic sites, with 18 operating as museums and attracting 729,000 annual visitors.