Officials closed down a major Chicago tourist attraction on Thursday following the appearance of cracks on its glass floor hundreds of metres above the ground.
The cracks came Wednesday night after a family of tourists from California stepped inside the tower's Ledge, a glass enclosure located roughly 457 metres above Chicago streets.
Alejandro Garibay and his family were on the 103rd level of the Willis Tower, taking in the sights and even joking with staff about the glass' integrity.
"They jokingly and confidently responded, 'It's unbreakable,' so we just went on," Garibay said in an interview with NBC. Garibay, his brother and two cousins stood and even sat down inside the Ledge before they started hearing the sounds of cracks.
Staff ushered them outside shortly after and closed down the attraction moments later.
Despite the images, officials say Garibay and his family weren't in any danger. In a statement to the Associated Press, representative from the building said the protective coating had cracked and not the actual sheets of glass underneath. Officials insist the cracks don't affect the "structural integrity" of the Ledge, which is designed to occasionally crack.
The Ledge's bottom is made up of 1,500-pound glass plates sealed together with a laminate so that in the even of a crack, the pieces stay intact even after impact, much like how car wind shields are design to break in the event of a collision, Gizmodo points out.
The attraction opened up in 2009 and was designed to withstand up yo four tons of pressure and able to hold up to 10,000 pounds, CBS reports.
The cracks came Wednesday night after a family of tourists from California stepped inside the tower's Ledge, a glass enclosure located roughly 457 metres above Chicago streets.
Alejandro Garibay and his family were on the 103rd level of the Willis Tower, taking in the sights and even joking with staff about the glass' integrity.
"They jokingly and confidently responded, 'It's unbreakable,' so we just went on," Garibay said in an interview with NBC. Garibay, his brother and two cousins stood and even sat down inside the Ledge before they started hearing the sounds of cracks.
Willis Tower's Ledge will be closed "while the investigation continues," repairs are finalized http://t.co/6QobxeYS55 pic.twitter.com/Yj7NYiBEFy
— Chicago Sun-Times (@Suntimes) May 29, 2014Staff ushered them outside shortly after and closed down the attraction moments later.
Despite the images, officials say Garibay and his family weren't in any danger. In a statement to the Associated Press, representative from the building said the protective coating had cracked and not the actual sheets of glass underneath. Officials insist the cracks don't affect the "structural integrity" of the Ledge, which is designed to occasionally crack.
The Ledge's bottom is made up of 1,500-pound glass plates sealed together with a laminate so that in the even of a crack, the pieces stay intact even after impact, much like how car wind shields are design to break in the event of a collision, Gizmodo points out.
The attraction opened up in 2009 and was designed to withstand up yo four tons of pressure and able to hold up to 10,000 pounds, CBS reports.