Sears Tower | "Willis Tower (formerly named and still commonly referred to as Sears Tower) is a 108-story, 1,451-foot (442 m) skyscraper in Chicago, Illinois. At the time of its completion in 1973, it was the tallest building in the world, surpassing the World Trade Center towers in New York, and it held this rank for nearly 25 years."
The Skydeck / Three glass bottom skyboxes (top right) on the west façade of Willis Tower at the 103rd floor / View looking down from glass balcony / The Sears Tower observation deck, called the Skydeck, opened on June 22, 1974. Located on the 103rd floor of the tower, it is 1,353 feet (412 m) high and is one of the most famous tourist attractions in Chicago. Tourists can experience how the building sways on a windy day.
The Sears Tower (now called the Willis Tower) in Chicago was the world's tallest building when it was built in 1973. Today it's the tallest building in North America. Learn more: http://architecture.about.com/od/skyscrapers/ig/World-s-Tallest-Buildings/Sears-Tower-.htm