Super Tall Skyscrapers - The Sears Tower

The Sears Tower is a supertall skyscraper in Chicago, Illinois, and the tallest building in the United States since 1973. By the measurement from the ground to the top of the antenna/spire it is the tallest building in the world.

There are four main categories in which the world's tallest building can be measured:

1. Height to the structural or architectural top (including spires and pinnacles, but not antennas, masts or flagpoles)

2. Height to the highest occupied floor

3. Height to the top of the roof

4. Height to the top of antenna

The height is measured from the pavement level of the main entrance. At the time, the Sears Tower held first place in the second, third and fourth categories.