Chicago City Hall is a 10-story building that houses the official seat of government of the City of Chicago in Illinois. Adjacent to the Richard J. Daley Center and the James R. Thompson Center, the building that includes Chicago City Hall houses the offices of the mayor, city clerk, and city treasurer; some city departments; aldermen of Chicago's various wards; and chambers of the Chicago City Council on the west side of the building. The building's east side is devoted to the various offices of Cook County, including chambers for the Cook County Board of Commissioners.
Situated on a city block bounded by Randolph, LaSalle, Washington Boulevard, and Clark Street, the 11-story structure was designed by the architectural firm Holabird & Roche in the classical revival style and built to replace and expand an earlier city hall. Its location has served as the center of city government from 1853 to 1871, and with a break due to the Great Chicago Fire, from 1885 to the present. The current hall was officially dedicated on February 27, 1911.