The Willis (formerly Sears) Tower, Chicago

The Willis Tower



Think, how do you let a 37-year-old skyscraper, has not been since 1998, the highest observation deck in the world?
You attach a series of the brilliant glass terrible box, collectively referred to as the window sill, the ancient Skydeck observation deck. You stand to support the illusion of the 103 stories above the ground, is a real crowd pleasing.
Inbox hung from a mobile steel frame, so that they can be retracted into the building, the window washbasin.