The John Hancock Center is a 100-story, 1,128-foot supertall skyscraper located in Chicago, Illinois. Located in the Magnificent Miledistrict, its name was changed to 875 North Michigan Avenue on February 12, 2018. Despite this, the building is still colloquially called the John Hancock Center.
It was constructed under the supervision of Skidmore, Owings and Merrill, with Peruvian-US chief designer Bruce Graham and Bangladeshi structural engineer Fazlur Rahman Khan. When the building topped out on May 6, 1968, it was the second-tallest building in the world and the tallest outside New York City. It is currently the fourth-tallest building in Chicago and the ninth-tallest in the United States, after One World Trade Center, the Willis Tower, 432 Park Avenue, the Trump Tower Chicago, the Empire State Building, the Bank of America Tower, 30 Hudson Yards and the Aon Center. When measured to the top of its antenna masts, it stands at 1,500 feet (457 m). The building is home to several offices and restaurants, as well as about 700 condominiums, and contains the third-highest residence in the world, after the Burj Khalifa in Dubai and the Trump Tower in Chicago. The building was named for John Hancock Mutual Life Insurance Company, a developer and original tenant of the building, which itself was named for the U.S. Founding FatherJohn Hancock. In 2018, John Hancock Insurance requested that its name be removed and the owner is seeking another naming rights deal.
One of the most famous buildings of the structural expressionist style, the skyscraper's distinctive X-braced exterior shows that the structure's skin is part of its "tubular system". This is one of the engineering techniques which the designers used to achieve a record height; the tubular system is the structure that keeps the building upright during wind and earthquake loads. This X-bracing allows for both higher performance from tall structures and the ability to open up the inside floorplan. Such original features have allowed 875 North Michigan Avenue to become an architectural icon. It was pioneered by Bangladeshi-American structural civil engineer Fazlur Khan and chief architect Bruce Graham.
The interior was remodeled in 1995, adding to the lobby travertine, black granite, and textured limestone surfaces. The elliptical-shaped plaza outside the building serves as a public oasis with seasonal plantings and a 12-foot (3.7 m) waterfall. A band of white lights at the top of the building is visible all over Chicago at night, and changes colors for different events. For example, at Christmas time the colors are green and red. When a Chicago-area sports team goes far in the playoffs, the colors are changed to match that team's colors.
The building is a member of the World Federation of Great Towers. It has won various awards for its distinctive style, including the Distinguished Architects Twenty-five Year Award from the American Institute of Architects in May 1999. In celebration of the 2018 Illinois Bicentennial, the John Hancock Center was selected as one of the Illinois 200 Great Places by the American Institute of Architects Illinois component (AIA Illinois) and was recognized by USA Today Travel magazine, as one of AIA Illinois' selections for Illinois 25 Must See Places.