Sears Tower's Ledge lets tourists step onto glass floors 1,353 feet above Chicago's sidewalks. Each box weighs 1,500 pounds, built from three layers of half-inch glass. It's engineered to hold 10,000 pounds. No one leans out a window to clean it. A motor pulls the whole box back on rails, straight into the building, then slides back out over the drop. The boxes are still open every day, right now.
Sears Tower's Glass Boxes Slide Into the Building
Sears Tower has a floor that is not really a floor. On the 103rd level, glass boxes jut out from the building over open air, and every day tourists walk out onto them anyway.
A Floor Made of Three Layers of Glass
The attraction is called the Ledge. It sits 1,353 feet above Chicago's sidewalks, on the tower now officially named Willis Tower.
Each glass box weighs 1,500 pounds on its own. The floor is built from three layers of half-inch glass, laminated into a single unit.
The whole structure is engineered to hold 10,000 pounds of visitors standing, jumping and taking photos at once.
No One Leans Out a Window to Clean It
Washing a pane of glass over 1,000 feet up sounds like a job for a window washer dangling from a rope. It is not.
Instead, the whole glass box rides on a motorized track. A motor pulls it backward on rails, straight into the building, floor and all.
Crews clean the glass from the inside, safely off the ledge. Then the motor pushes the box back out over the drop, ready for the next tourist.
The Time the Floor Made Headlines
In 2019, a family standing on the Ledge heard a crack under their feet. Photos of the cracked glass quickly spread online.
Tower officials clarified what had actually happened. Only a protective coating on top of the glass had cracked, not the structural glass itself.
Officials said no visitors were ever in danger. Crews replaced the coating and the Ledge reopened.
It was not the first time. A similar coating crack in 2014 also made headlines, with the same result: a quick repair and no injuries.
Still Open, Every Day
The Ledge opened in 2009, designed by Skidmore, Owings and Merrill, the same firm that designed the original Sears Tower.
More than a decade later, the boxes still slide in and out for cleaning, and tourists still line up to stand on them.
Right now, on the 103rd floor of Chicago's tallest building, someone is looking straight down through the floor at the street 1,353 feet below.
Frequently Asked Questions
How high up is the Sears Tower Ledge?
How do they clean the glass floor on the Sears Tower Ledge?
How much weight can the Ledge glass floor hold?
Did the glass floor on the Sears Tower Ledge ever crack?
When did the Ledge open at Sears Tower?
Verified Fact
Verified Sep 1, 2026 · 5 sources checked
Source: Skydeck Chicago (Willis Tower)Show verification details
Claims checked
- The Ledge is a set of retractable glass balconies on the 103rd floor of Sears Tower, now officially Willis Tower, 1,353 feet above the street
- Each glass box is built from three layers of half-inch glass and is engineered to hold up to 10,000 pounds
- Weight of each glass box corrected to 1,500 pounds (was 7,500 pounds)
- The boxes retract into the building on a motorized rail system for cleaning, then slide back out
- In 2019 and 2014 a protective coating cracked while visitors stood on it; officials confirmed the structural glass was unaffected and no one was in danger
Sources: Willis Tower Skydeck, MTH Industries, CNN, ABC7 Chicago, CBS News
Related Topics
More from Places & Culture
View all Places & Culture →
