The John Hancock Center is a 100-story, 1,128-foot (343.7 m) supertall skyscraper at 875 North Michigan Avenue, 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 second tallest building in the world and the tallest outside of New York City.