Sears Tower in Chicago is fitted with an observation area jutting 1.4m from the building

A series of glass observation boxes have been added to the 103rd floor of the Sears Tower in Chicago, the tallest building in the Western Hemisphere.

The Skydeck observation area, which has been dubbed The Ledge, includes glass bays that extend 1.4m out from the building.

Sears Tower

The boxes, engineered by Halcrow Yolles, are built to withstand wind pressures of 125 pounds per square foot and loads of up to five tons.