O'Hare International Airport is an airport on the edge of Chicago, Illinois. It is in the Chicago neighborhood O'Hare. It is one of the largest airports in both the United States and the world. It is a "hub" for both United Airlines (its second largest hub) and American Airlines, meaning that flights from many cities come and go from the airport daily.  It gets the most international flights of any American airport not on the East or West Coast.

The Federal government of the United States reduces the amount of delayed flights in the airport in order to shift the burden of domestic flights at Hartsfield–Jackson Atlanta International Airport.

United Airlines (including United Express) is the largest airline at O'Hare, carrying over 45% of passengers. O'Hare is the second-largest hub for United, after Houston-Bush. American Airlines (including American Eagle) has the second largest operation at O'Hare, carrying 37.08% of passengers. O'Hare is American Airlines' third-largest hub, after Dallas/Fort Worth and Charlotte-Douglas.

O'Hare has been voted the "Best Airport in North America" for 10 years by two separate sources: Readers of the U.S. Edition of Business Traveler Magazine (1998–2003) and Global Traveler Magazine (2004–2007). Travel and Leisure magazine's 2009 "America's Favorite Cities" ranked Chicago's Airport System (O'Hare and Midway) the second-worst for delays, New York City's airport system (JFK, Newark Liberty, and LaGuardia) being the first. O'Hare currently accounts for over a sixth of the nation's total flight cancellations.

The O'Hare Airport is 668 feet (204 meters) above sea level.

It is operated by the City of Chicago Department of Aviation. Most of O'Hare Airport is in Cook County. However, a section of the southwest part of the airport is in DuPage County. The Cook County portion is located within a section of the city of Chicago contiguously connected to the rest of the city via a narrow strip of land about 200 feet (61 m) wide, running along Foster Ave. from the Des Plaines River to the airport. This land was annexed into the city limits in the 1950s to assure the massive tax revenue associated with the airport being part of the city. The strip is bounded on the north by Rosemont and the south by Schiller Park.

History
The airport was constructed in 1942–43. It was made as a manufacturing plant for airplanes during World War II. The site was chosen for its proximity to the city and transportation. The two-million square-foot (180,000 m²) factory needed easy access to the workforce of the nation's then-second-largest city, as well as its extensive railroad infrastructure. Orchard Place was a small nearby farming community.

Douglas Company's contract ended in 1945 and though plans were proposed to build commercial aircraft, the company ultimately chose to concentrate production on the west coast. With the departure of Douglas, the airport took the name Orchard Field Airport. That was the source of its three-letter IATA code ORD.

In 1945, the facility was chosen by the city of Chicago as the site for a facility to meet future aviation demands. Matthew Laflin Rockwell (1915–1988) was the director of planning for the U.S. Army Corps of Engineers and responsible for the site selection and design of O'Hare International Airport. He was the great grandson of Matthew Laflin, a founder and pioneer of Chicago. The architect of the airport was Gertrude Kerbis.

The O'Hare is currently undergoing the largest construction projects in the United States.

In March 2014, a Blue Line train was derailed and crashed at the O'Hare train station, injuring 32 people.

Transportation
 Road vehicles enter and exit via I-190, which branches off I-90 (the Kennedy Expressway) leading to downtown Chicago. Cars may also access the airport locally from Mannheim Road, the airport's eastern boundary. Aside from cargo access on its south side, all airport traffic travels through the east side of the airport. Local residents sometimes refer to I-190 as "the world's busiest Cul-de-sac" as a result of the one way access.
 Subway trains from the Blue Line of the Chicago Transit Authority's 'L' depart the terminal from an underground station that opened on September 3, 1984.
 Commuter trains from the Metra North Central Service stop at the O'Hare Transfer station, which is connected to the Airport Transit System via a shuttle bus.
 Taxi and Limo Services also provide transportation to/from Chicago O'Hare Airport.

Accidents
1057 deaths have happened as a result of accidents to or from Chicago O'Hare.

Airlines
The following airlines fly to O'Hare International Airport:

Aer Lingus
Aeroméxico
Air Canada
Air Choice One (hub)
Air France (seasonal)
Air India
Alaska Airlines
Alitalia (seasonal)
All Nippon Airways
American Airlines (hub)
Austrian Airlines 
Avianca
British Airways
Cathay Pacific
Cayman Airways (seasonal)
China Eastern Airlines 
Copa Airlines
Delta Air Lines
Emirates
Etihad Airways
EVA Air 
Finnair 
Frontier Airlines (focus city)
Hainan Airlines 
Iberia Airlines
Icelandair 
Interjet 
Japan Airlines
JetBlue Airways
KLM
Korean Air
LOT Polish Airlines
Lufthansa
Qatar Airways 
Royal Jordanian
Scandinavian Airlines
Spirit Airlines (focus city)
Turkish Airlines
United Airlines (hub)
Virgin America
Virgin Atlantic Airways (seasonal)
Volaris
WestJet (seasonal)
WOW Air (starts July 13) 
XTRA Airways

The following airlines used to fly to O'Hare International Airport:

Aeroflot
Air Florida
Air One
Air Ukraine 
Aviacsa
Aviateca
Braniff International Airways
BMI
Canadian Airlines
Continental Airlines
Czech Airlines
Eastern Air Lines
Ecuatoriana
Finnair
Iceland Express
Mexicana de Aviacion 
National Airlines
Northwest Airlines
Norwegian Air Shuttle
Pakistan International Airlines
Pan American World Airways
Philippine Airlines
Qantas
Sabena
Swissair
TACA Airlines
TAESA
TAROM Romanian Airlines
TWA
USA3000 Airlines
US Airways
Varig Brazilian Airlines
Virgin Atlantic Airways 
Wardair Canada

Gallery

References

Other websites

 O'Hare International Airport  (official web site)
 O'Hare airport Modernization plan 
 O'Hare Modernization Program (official web site)
 41st ward map (official city web site)
 The Northwest Chicago Historical Society's page on O'Hare 
 openNav: ORD / KORD charts

Airports in Chicago
1944 establishments in the United States
1940s establishments in Illinois