The John Hancock Center is a 100-story, 1,127-foot (344 m) tall skyscraper, located at 875 NorthMichigan Avenue in the Streeterville area of Chicago, Illinois, United States. It was constructed under the supervision of Skidmore, Owings and Merrill, with chief designer Bruce Graham and structural engineer Fazlur Khan. When the building topped out on May 6, 1968, it was the tallest building in the world outside New York City. It is currently the fourth-tallest building in Chicago and the seventh-tallest in the United States (after One World Trade Center, the Willis Tower, the Trump Tower Chicago, theEmpire State Building, the Bank of America Tower, and the Aon Center). When measured to the top of its antenna masts, it stands at 1,506 feet (459 m). The building is home to offices and restaurants, as well as about 700 condominiums, and contains the third highest residence (above adjacent ground level) in the world, after the Trump Tower (also in Chicago), and the Burj Khalifa (in Dubai). The building was named for John Hancock Mutual Life Insurance Company, a developer and original tenant of the building, and has the nickname "Big John".

The 95th floor has long been home to a restaurant, the latest tenant being "The Signature Room on the 95th Floor". Diners can look out at Chicago and Lake Michigan. The Observatory attraction (called "360 Chicago" since March 2014) competes with the Willis Tower's Skydeck across town. John Hancock Center is in the heart of Michigan Avenue, a prime tourist hotspot in Chicago, while the Willis Tower is in the financial district. John Hancock Observatory allows a 360° view of the city, up to four states, and a distance of over 80 miles (130 km). The Observatory has Chicago's only open-air SkyWalk and also features a free multimedia tour in six languages, narrated by actor David Schwimmer. The 44th-floorsky lobby features America's highest indoor swimming pool.

Source: http://en.wikipedia.org/wiki/John_Hancock_Center