The John Hancock Center in Chicago was completed in 1969.
Now officially known as 875 North Michigan Avenue, the 100-story skyscraper was designed by Skidmore, Owings & Merrill. Architect Bruce Graham and structural engineer Fazlur Rahman Khan developed its distinctive exterior X-bracing, a visible expression of the building’s innovative structural system.
The tower topped out in 1968 and was completed and opened in 1969. At 1,128 feet, or about 344 meters, it became one of the world’s tallest buildings and a defining landmark of Chicago’s Magnificent Mile. Its paired antenna masts extend the overall height much farther.
A frequent source of confusion is the building’s name: many people still call it the John Hancock Center, although the official address-based name changed. It is also sometimes mixed up with the nearby Willis Tower, completed in 1973. The Hancock’s dark façade and diagonal braces remain among Chicago’s best-known examples of structural expressionism.