In 1876, Forest Park was created from 1,371 acres of land west of downtown St. Louis. By the 1890s, the public park was widely used for recreation with bicycle paths, baseball diamonds and lawn tennis courts. An expanded lake provided park goers with an opportunity for boating in the summer and skating in the winter. Funds were raised to develop the Saint Louis Zoo by the Forest Park Zoological Association.

The western half of the metropolitan park was used as the site for the Louisiana Purchase Exposition in 1904. Today, the Saint Louis Art Museum occupies one of the few remaining structures built for the Fair. The Missouri Historical Society is comprised of the Emerson Electric Center and the Jefferson Memorial Building. The building was the first memorial built to honor Thomas Jefferson and was funded with proceeds from the 1904 Fair.

A natural amphitheater near Art Hill was developed as The Muny in 1917 with proceeds from a theatrical production called the Pageant and Masque which was performed on a stage built over part of the Grand Basin.

In 1936, an Art Deco-style Conservatory opened in Forest Park. The Jewel Box is surrounded by rose gardens, lily ponds, statuary and monuments and houses seasonal displays.

The site of a razed Mounted Police Station became space for the McDonnell Planetarium which was completed in 1963. In 1984, the city sold the Planetarium to the Museum of Science and Natural History. The building, renamed the Saint Louis Science Center, is connected by a highway overpass and tunnel to its new headquarters, south of Forest Park.

Forest Park is used by more than 13 million visitors a year. Forest Park Forever was founded in 1986 to work in partnership with the Department of Parks, Recreation & Forestry to rehabilitate and maintain the Forest Park as the "Crown Jewel" of the metropolitan area.