Landmark opened in 1973 with original tenant Sears Roebuck & Co. CHICAGO, Illinois (CNN) -- Sears Tower is history. As of Thursday, the iconic Chicago, Illinois, skyscraper is now named Willis Tower.

Willis Tower and its Skydeck sit above South Wacker Drive on the western edge of the Loop. You'll find the Quincy/Wells L station nearby, as well as several bus stops and a parking garage.

An curved arrow pointing right. The Ledge is a glass box on the 103rd floor of the Willis Tower, the eighth-tallest building in the world and the tallest building in the Western hemisphere.

One step at a time, more than 2,000 people from all around the world converged on Willis Tower to climb up the world's 12th tallest building. Sunday marked the 16th SkyRise Chicago, which raises ...

Chicago is home to one of the tallest buildings in the world: the Willis Tower. So tall that on a windy day, the topmost floors can sway as much as three feet. But what keeps it from falling?

Chicago is home to one of the tallest buildings in the world: the Willis Tower. So tall that on a windy day, the topmost floors can sway as much as three feet. But what keeps it from falling?