The Washington Park Historic District in the city of Ottawa, Illinois, is also known as Washington Square. Occupying over 12 acres of land, the historic district is listed in the U.S. National Register of Historic Places. While the Washington Park is a part of the historic district, other historic properties that are a part of it include 3rd Appellate Court, Civil War Memorial, Congregational Church, Christ Episcopal Church, Lincoln-Douglas debate site, Popcorn wagon from the 1890s, and William Reddick Mansion.