Sears Tower - A Building Book From The Chicago Architecture Foundation

The Nation's Largest Retailer wanted the largest headquarters in the nation, and they got it -- in spades. Designed by Skidmore, Owings & Merrill (SOM), the 110-story, anodized aluminum-clad Sears Tower occupies three acres in the West Loop. The bundled-tube construction allowed for more windows and more corner offices per square foot. The total area within the Tower is 4.4 million square feet; the Sky Deck on the 103rd floor offers tremendous views and welcomes more than 1 million visitors yearly.

When SOM realized that their design was only ten stories short of what was supposed to be the record-breaking height of the World Trade Center then under construction (1,368 feet), they broke the record, coming in at 1,454 feet. The move of Sears and Roebuck employees into the Tower was the biggest corporate move in American history. In the late 1980s Sears and Roebuck left the building, but it continues to thrive, a timeless monument to American ingenuity.