From Wikipedia:
The Willis Tower (formerly the Sears Tower) is a 108-story, 1,451-foot (442.3 m) skyscraper in Chicago. […] At completion in 1974, it surpassed the World Trade Center in New York City to become the tallest building in the world, a title that it held for nearly 25 years. It was also the tallest building in the Western Hemisphere for 41 years, until the One World Trade Center surpassed it in 2013, and had the highest occupiable floor until surpassed by the Central Park Tower in 2022.
Inside Willis Tower, the font Aktiv Grotesk was used for some of the signage. This expands to the new Willis Tower Skydeck experience designed by Thinc Design (with Squint/Opera), SOM – Skidmore Owings & Merrill, and Chicago Scenic Studios (with DSA Signage), completed in 2021, which includes an exhibition titled Story of Chicago.