First of all: Everyone's fine. Here's why the glass chamber has experienced multiple instances of shattering. The Willis Tower is the second tallest building in the United States, and its Skydeck observatory, on the 103rd floor, lets visitors step out over the city while supported only by a few layers of glass. It's designed to be a safe, if terrifying, tourist experience—but after cracking once in 2014, the protective glass flooring on the observatory deck cracked again this week. Read Full Story
A trip to the top of the tallest building in Chicago turned into an even more harrowing experience in the sky for some visitors when a protective coating on the glass-floored balcony began to crack beneath their feet.