Harold Washington Library, Chicago (must see)
The Harold Washington Library Center is the central library for the Chicago Public Library System. It is named for former Mayor Harold Washington. It is approximately 756,640 square feet (70,294 m2). The Harold Washington Library opened on October 7, 1991. After the refurbishment of the Chicago Cultural Center in 1977, where the central library had been housed, much of the library's collection was placed into storage. Upon the building's completion in 1991, the new Mayor Richard M. Daley named the building in honor of the now-deceased Washington, an advocate of reading and education among Chicagoans as well as an advocate of the library's construction. Since completion, the Library has appeared in the Guinness Book of Records as the largest public library building in the world.
Sight description based on wikipedia