Chicago City Hall is the official city hall of the City of Chicago in Illinois, United States. Next to the Richard J. Daley Center and the James R. Thompson Center, the building that includes Chicago City Hall has the offices of the mayor. The building's east side (called the County Building) is for offices of Cook County. It is on a city block bounded by Randolph, LaSalle, Washington, and Clark streets. The 11-story building was designed by the architectural firm Holabird &amp; Roche in the classical revival style. The building was officially dedicated on February 27, 1911.