Citigroup Center is a 42 story, 588-foot (180 m) skyscraper

Skyscraper

A skyscraper is a tall, continuously habitable building of many stories, often designed for office and commercial use. There is no official definition or height above which a building may be classified as a skyscraper...

 in Chicago

Chicago

Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

, Illinois

Illinois

Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...

. Located at 500 W. Madison (between Clinton and Canal Streets), the structure was designed by the architecture firm Murphy/Jahn

Helmut Jahn

Helmut Jahn is a German-American architect, well known for designs such as the US$800 million Sony Center on the Potsdamer Platz, Berlin, the Messeturm in Frankfurt and the One Liberty Place, formerly the tallest building in Philadelphia, Pennsylvania, and Suvarnabhumi Airport, an international...

 in a late modernist

Modern architecture

Modern architecture is generally characterized by simplification of form and creation of ornament from the structure and theme of the building. It is a term applied to an overarching movement, with its exact definition and scope varying widely...

 style. The building, previously named the Northwestern Atrium Center, was constructed between 1984 and 1987 on the air rights

Air rights

Air rights are a type of development right in real estate, referring to the empty space above a property. Generally speaking, owning or renting land or a building gives one the right to use and develop the air rights....

 obtained by the destruction of the headhouse of the 1911 North Western Station. Citigroup Center contains retail shopping and offices, and is connected to the platforms of the Ogilvie Transportation Center

Ogilvie Transportation Center

The Richard B. Ogilvie Transportation Center is a passenger terminal in downtown Chicago, Illinois, USA, serving the three commuter rail lines of Metra's Union Pacific District, which approach the terminal elevated above street level. It occupies the lower floors of the Citigroup Center...

 (which unofficially continues to be called Northwestern Station) and thousands of Metra

Metra

Metra is the commuter rail division of the Illinois Regional Transportation Authority. The system serves Chicago and its metropolitan area through 240 stations on 11 different rail lines. Throughout the 21st century, Metra has been the second busiest commuter rail system in the United States by...

 commuters use the facility every day.

Orbitz

Orbitz

Orbitz Worldwide, Inc. is an Internet travel company headquartered in the Citigroup Center in Near West Side, Chicago, Illinois. Through its primary web site Orbitz.com, Orbitz Worldwide enables travelers to research, plan and book a broad range of travel products, facilitating 1.5 million flight...

 Worldwide (NYSE: OWW) maintains its worldwide headquarters

Headquarters

Headquarters denotes the location where most, if not all, of the important functions of an organization are coordinated. In the United States, the corporate headquarters represents the entity at the center or the top of a corporation taking full responsibility managing all business activities...

 in the building, on three floors.

Shooting

On 8 December 2006 a man opened fire in a law office located on the 38th floor of the Citigroup Center. Four people, including the gunman, were killed. One person survived.

See also

• List of buildings
• List of skyscrapers
• List of tallest buildings in Chicago
• List of tallest buildings in the United States
• World's tallest structures