The Harold Washington Library Center is the central library for the Chicago Public Library System. It is located just south of the Loop 'L', at 400 South State Street in Chicago, in the U.S. state of Illinois. It is a full-service library and is ADA compliant. Opened in 1991, it functionally replaced the city's 19th-century central library. The postmodernist building contains approximately 756,000 sq ft (70,200 m2) of work space. The total square footage is approximately 972,000 sq ft (90,300 m2) including the rooftop winter-garden event space. It is named in honor of former Mayor Harold Washington.