Tourists to Sears Tower in Chic ago will soon be able to enjoy a view normally reserved for Spiderman.
Glass balconies are being installed near the top of the tallest tower in America, offering dizzyness-inducing views 102-stories straight down.
Bosses for the 442m (1,450ft) tower say there will be three layers of half-inch thick glass and that the balconies will be able to hold about five tons.
The idea for "The Ledges" is said to have come from the hundreds of forehead prints left on windows at the top of the tower which attracts 1.3 million visitors each year.
A spokesperson for Sears Tower said: "Visitors are constantly trying to catch a glimpse below. Now they have a unique and unobstructed view of the city.
"The balconies provide unobstructed views of miniature-looking people, taxis and bridges from glass floors 1,353 feet over Wacker Drive and the Chicago River."
Original Sears Tower architecture firm Skidmore, Owings and Merrill were called in to design the new feature which will retract into the building to allow easy access for cleaning and maintenance.
They are using low-iron, clear glass which is fully tempered and heat-soaked for durability and say each balcony will be able accommodate four to five people at a time when they open in June.
The move is part of a multi-million dollar update of the tourist attraction which will also see new exhibits highlighting the towers history.
Sears Tower - at 108-stories and 442m - was the tallest building in the world when it was completed in 1973.
