You're thinking of the Hyatt Regency (now Sheraton): https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse https://en.wikipedia.org/wiki/Hyatt_Regency_wa

You're thinking of the Hyatt Regency (now Sheraton): https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse It was not as you describe; the original design was absolutely not correct. The original design was additionally so difficult to implement in reality that one of the manufacturers of the structural parts proposed a design change - one that made the flaws of the original twice as bad - that architects approved without any actual review. I've been there several times, since it's a popular spot for conferences - looking up at the doors to nowhere in the lobby atrium is haunting.