<Tr> <Td_colspan="2"> Source: Federal Aviation Administration, Passenger traffic </Td> </Tr> <P> Washington Dulles International Airport (/ ˈdʌlɪs / DUL - iss) (IATA: IAD, ICAO: KIAD, FAA LID: IAD) is an international airport in Loudoun and Fairfax counties in Virginia, United States, 26 miles (42 km) west of downtown Washington, D.C. The airport serves the Baltimore--Washington metropolitan area, centered on the District of Columbia . The airport is named after John Foster Dulles, the 52nd Secretary of State who served under President Dwight D. Eisenhower . The Dulles main terminal is a well - known landmark designed by Eero Saarinen . Operated by the Metropolitan Washington Airports Authority, Dulles Airport occupies 13,000 acres (52.6 km) straddling the Loudoun - Fairfax line . Most of the airport is in the unincorporated community of Dulles, in Loudoun County, with a small portion in the unincorporated community of Chantilly in Fairfax County . </P> <P> Dulles is one of the three major airports in the larger Baltimore--Washington metropolitan area with more than 21 million passengers a year . Dulles has the most international passenger traffic of any airport in the Mid-Atlantic outside of the New York metropolitan area, including approximately 90% of the international passenger traffic in the Baltimore - Washington region . On a typical day, more than 60,000 passengers pass through Washington Dulles to and from more than 125 destinations around the world . However, Dulles Airport now ranks behind both Baltimore - Washington International Airport (BWI) and Ronald Reagan Washington National Airport (DCA) in total annual passenger boardings . </P> <P> Prior to World War II, Hoover Field was the main commercial airport serving Washington . It was replaced by Washington National Airport in 1941 . After the war, in 1948, the Civil Aeronautics Administration began to consider sites for a second major airport to serve the nation's capital . Congress passed the Washington Airport Act in 1950 to provide funding for a new airport in the region . The initial CAA proposal in 1951 called for the airport to be built in Fairfax County near what is now Burke Lake Park, but protests from residents, as well as the rapid expansion of Washington's suburbs during the time, led to reconsideration of this plan . One competing plan called for the airport to be built in the Pender area of Fairfax County, while another called for the conversion of Andrews Air Force Base in Prince George's County, Maryland . </P>

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