CHICAGO — Visitors at the Willis Tower got a sky-high scare after one of the SkyDeck's glass ledges shattered on Monday.
According to CNN, the SkyDeck features clear observation boxes 103 stories up, that give tourists spectacular views of Chicago.
On Monday, visitors experienced a heartstopping moment after the glass began to crack right under their feet.
Witness Jesus Pintado captured the terrifying scene on video, showing the glass floor of the ledge splintered into tiny pieces.
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.
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.
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.