By DAILY MAIL REPORTER
No fear: A woman performs a handstand in one of the boxes that form 'the ledge', which stand 1,353ft above the Chicago skyline
Jutting four and a half feet outside of the Willis Tower in Chicago, 'The Ledge' is definitely not for the faint-hearted.
But trying telling that to this daredevil who performed a handstand 1,353 feet above the city's skyline.
The unnamed man performed the trick in one of the four glass boxes that are giving unparalleled views across the Windy City from America's tallest building.
Extending out of the 103rd floor of the 110-storey building, each one of the fully retractable boxes that make up The Ledge weighs in at 1,500 pounds.
The three inch glass gives never-before-seen views of the city, and allows visitors to see for 50 miles around.
Spectacular: The boxes that jut out from the Willis Tower provide never-before-seen views of the city, and allows spectators to see for 50 miles around
Inspired by the film 'Ferris Bueller's Day Off', where the title character encourages his friends to lean their heads against the glass of the Willis Tower's public Skydeck, The Ledge has quickly become a city favourite.
'You only need to see the forehead prints on the windows to know that visitors are constantly trying to catch a glimpse below, said Randy Stancik, general manager of the Skydeck Chicago.
Don't look down: Visitors are protected from the 103-storey drop by three inches of glass
Opened in 1974, the Willis Tower was formerly known around the world as the Sears Tower and is still the tallest building in the United States.
'The Ledge's glass boxes extend from the Skydeck, providing unobstructed views straight down,' said a spokesperson for the Skydeck at the Willis Tower.
'Each box provides unobstructed views of people, taxis, boats and bridges over Wacker Drive and the Chicago River.'
America's tallest: The Willis Tower, formerly the Sears Tower, is the world's fifth tallest building. The four viewing boxes can be seen on the third windows down from the top