They thought it was cracking under them, 103 stories above the ground. (Published Tuesday, July 28, 2009) 
 
 Alejandro Garibay, his brother, and two cousins were in the glass enclosure that juts out of the west side of the building shortly before 10 p.m. Wednesday when Garibay said they heard cracking. "They jokingly and confidently responded, 'It's unbreakable,' so we just went on," said Garibay. But Willis Tower spokesman Bill Utter said the cracking they felt was simply a scratch-resistant layer on the glass “doing what it’s designed to.” It did not affect the structural integrity of the box, he said. Occasionally, the coating will crack, as it is designed to in order to protect the surface of the glass," Rehme said in a statement. The one in the northwest corner of Willis Tower remained closed — but officials said it would open Friday morning after workers replaced the cracked layer of glass that protects three half-inch thick layers that can withstand 10,000 pounds. Turns out it was just the protective coating, but they didn’t know that at the time. The move comes hours after cracks appeared in what the official said was a coating designed to prevent scratches on the glass. The Ledge was closed, she said, only “out of extreme caution.” 
 
 Even as news of the alleged “cracks” spread — tourists could be heard talking openly about them on the Willis Tower Skydeck — several visitors echoed Plantilla’s indifference to them. Breakdancing on the Ledge 
 
 Some people won't even brave stepping out on the Ledge, but one guy clearly moves to the beat of his own drum.
– Perhaps the Windy City is tired of pesky tourists, because it scared the bejeezus out of a few last night: As NBC Chicago reports, Alejandro Garibay and three members of his family stepped out on "the Ledge" at the Willis Tower—four glass balconies on the 103rd floor Skydeck that jut out four feet, allowing visitors to look down 1,353 feet through a glass floor that can allegedly hold five tons—when they heard a cracking sound and saw the glass floor cracking beneath their feet. Garibay says they scooted off the balcony and called workers. "They were totally shocked and asked us to step away and then proceeded to start calling staff and techs and I don't know who else," says Garibay. "When we pulled our phones to start recording and take pictures they asked us to leave right away." Tower officials say it's no big deal and in fact the glass was doing what it was supposed to do: "Occasionally this happens, but that’s because we designed it this way," says a rep. "Whatever happened last night is a result of the protective coating doing what it’s designed to." He says that it was that top coating that cracked, and not anything structural; regardless, the Chicago Sun-Times notes that one of the ledges was indeed roped off this morning, its floor covered with carpet. Over at Gizmodo, Kelsey Campbell-Dollaghan runs down why it really wasn't a big deal, noting that the top layer of safety glass is called safety glass "because it stays intact, even when it shatters."