It's History - When Chicago built the Tallest Building in the World - The story of Sears Tower

An informative video about the history of the "Sears Tower" and its construction. The video also explains the name change of the building in 2009 when it was renamed the "Willis Tower"

MegaStructures - Willis Tower (Sears Tower) (National Geographic Documentary)

This video looks back into the history and construction of the Willis Tower (formerly Sears Tower), a 108-storey, 1451-foot (442 m) skyscraper in Chicago, Illinois. At the time of its completion in 1973, it was the tallest building in the world (for nearly 25 years). More than 25,000 people walk into the Sears Tower every day it takes 104 elevators some double-decker to transport workers and visitors to the 110 floors.