Towering over the windy city of Chicago, the Willis Tower (formerly known as Sears Tower) was once the tallest building in the world upon its completion in 1973. Sears, Roebuck, & Company commissioned Skidmore, Owings, & Merrill to design an office building that would house their headquarters and the many offices they had scattered around Chicago in one building. The design also had to incorporate extra office space for the anticipated future growth of the company.
More on the Willis Tower after the break.



























































