Which building in Chicago's Federal Plaza was also designed by Mies van der Rohe?

The John Kluczynski Building, located in Chicago's Federal Plaza, is indeed designed by Mies van der Rohe, a prominent architect known for his contributions to modern architecture and structural expressionism. This building showcases his characteristic design principles, including the use of simple geometric forms and an emphasis on the connection between the interior spaces and the exterior environment.

Mies van der Rohe was greatly influential in shaping the architectural landscape of Chicago and is well-known for other significant works, but the John Kluczynski Building stands out as an example of his minimalist style and innovative use of materials. The building features a sleek, modernist façade that aligns with his philosophy of “less is more,” highlighting his skill in creating functional yet aesthetically pleasing structures.

The other buildings listed, such as the Sears Tower (now known as Willis Tower) and the Chicago Board of Trade Building, were designed by different architects and do not represent Mies’ signature contributions. Therefore, the John Kluczynski Building is the correct and notable choice in identifying the work of Mies van der Rohe within Chicago’s architectural context.