CHICAGO — Visitors at the Willis Tower got a sky-high scare after one of the SkyDeck's glass ledges shattered on Monday.<br /><br />According to CNN, the SkyDeck features clear observation boxes 103 stories up, that give tourists spectacular views of Chicago.<br /><br />On Monday, visitors experienced a heartstopping moment after the glass began to crack right under their feet.<br /><br />Witness Jesus Pintado captured the terrifying scene on video, showing the glass floor of the ledge splintered into tiny pieces.<br /><br />It's not the first time a SkyDeck ledge has cracked, either. People were panicking just as hard when the same thing happened in May 2014.<br /><br />The ledge itself can hold up to five tons, and is composed of three layers of glass each about one half inch thick and coated with a protective layer.<br /><br />The Willis Tower told CBS the glass that splintered was the protective layer, which acts more or less like a screen protector. It posed no immediate danger, and was replaced later that night.
