Most often being left more in their natural state, the Forest Preserves have a different purpose from urban parks; also they generally do not contain organized recreational facilities such as tennis courts or softball diamonds. They do contain hiking, bicycling, and riding trails, as well as facilities for nature and group activities, and they are heavily used for picnicking. They are administered by the Forest Preserve District of Cook County, a special taxation district that crosses municipal boundaries. The districts headquarters is located in River Forest near Harlem Avenue and Lake Street.