Chicago Federal Center
The Chicago Federal Center is actually a collection of three of Mies's buildings. The rigid simplicity of the black geometry is considered one of the finest expressions of the 'Second Chicago School'. According to the AIA guide of Chicago: "Mies's uncompromising devotion to principle, together with his vaunted sensitivity to proportion and structural detail, and, in this case, the organizational scale, combine to give the complex a monumental urban presence. Both towers are curtain-wall structures, characteristic of the high-rise design of Mies's American period. Their steel frames, suppressed behind uniform walls of glass and steel, are marked off by projecting steel I-beam mullions. The Post Office, a unitary space with a central core, is similarly typical of Mies's reductivist concept of the single-storey pavilion. Externally thin yet powerful structural columns of steel brace enormous panes of tinted glass." The Flamingo by Alexander Calder is contained within the plaza.