Zifeng Tower (a.k.a. Greenland Center-Zifeng Tower or Greenland Square Zifeng Tower, formerly Nanjing Greenland Financial Center) is a 450-metre (1,480 ft) skyscraper completed in 2009 in Nanjing, China. The 89-story building comprises retail and office space in the lower section, and restaurants, a hotel, and a public observatory near the top. The tower’s stepping is functional, helping separate these sections.
Architectural firm Skidmore, Owings and Merrill designed the building led by Adrian Smith.[source]