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Standing Strong in the Windy City

As part of its Skyline Stories video series, the Chicago Architecture Foundation highlights Willis Tower as a seminal skyscraper that helped transform supertall building design. Formerly known as the Sears Tower, the Chicago icon is comprised of nine squared tubes, each rigid within itself without internal supports. The tubes are bundled together and terminate at varying heights, creating a multi-tiered, wind-resistant form. Watch the video

(Source: youtube.com, via skidmoreowingsmerrill)