Chicago: Sears Tower - View from Southwest

In June 2000, Sears Tower once again became the world's tallest building from base to tip of antenna, when a 22 ft. extension was added to one of the tower's two broadcast antennas. It had already regained its title as the tallest building in the world in two of four vcategories under revised 1997 international guidelines. Although it no longer has the tallest structural height (Petrons Towers in Kuala Lumpur has that distinction), it does have the highest occupied floor and also the heightest height to the rooftop.

Sears Tower, opened in 1974, was designed by Bruce Graham, a partner at the Chicago architectural firm of Skidmore, Owins and Merrill, with the assistance of chief engineer Fazlur Khan. Construction of the innovative building took three years, employing 1600 people. More than 110 concrete caissons anchored in bedrock support the tower's 222,500 tons. Today, the tower contains 3.5 million sq. ft. of office space, more than 100 elevators, and enough telephone cable to encircle the Earth twice. The elevator to the Skydeck travels at a stoamch chruning 16000 ft per minute.

In 2007, the Sears Tower was ranked #42 on the AIA 150 America's Favorite Architecture list.