Before World War II, Hoover Field was the main commercial airport serving Washington, on the site now occupied by the Pentagon and its parking lots.

[20] 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.

As a result of the site selection, the unincorporated, largely African-American community of Willard, which once stood in the airport's current footprint, was demolished, and 87 property owners had their holdings condemned.

[24] The main terminal was designed in 1958 by famed Finnish-American architect Eero Saarinen, and it is highly regarded for its graceful beauty, suggestive of flight.

The first midfield terminal that included gates and jetbridges was constructed in 1985 when New York Air and other airlines began hub operations at Dulles.

[26][27] The design included a landscaped man-made lake to collect rainwater, a low-rise hotel, and a row of office buildings along the north side of the main parking lot.

The design also included a two-level road in front of the terminal to separate arrival and departure traffic and a federally owned limited access highway connecting the terminal to the Capital Beltway (I-495) about 17 miles (27 km) to the east; the highway system eventually grew to include a parallel toll road to handle commuter traffic and an extension to connect to I-66.

[28] By 1985 the original design, featuring mobile lounges to meet each plane, was no longer well-suited to Dulles's role as a hub airport.

[35][36] In the short term, United Airlines has constructed a 20,000 square foot (1,900 m2) buildout on Concourse C between gate C18 and the AeroTrain entrance for use as a Polaris Lounge for international passengers.

[38] Decades-old rules set by Congress that limit the number of takeoffs and landings, as well as distance of routes, at Reagan Airport were intended in part to keep more flights at Dulles.

The solar panels would cover more than 835 acres (338 ha) on land, equivalent to the consumption of more than 37,000 Northern Virginia homes during peak production.

[40] The first scheduled flight at Dulles was an Eastern Air Lines Lockheed L-188 Super Electra from Newark International Airport in New Jersey on November 19, 1962.

[45] On December 26, 1973, President Richard Nixon flew from Dulles to Los Angeles on board a United Airlines McDonnell Douglas DC-10 commercial flight instead of on Air Force One.

[47][48][49] On June 12, 1983, the Space Shuttle Enterprise arrived at Dulles atop a modified Boeing 747 after touring Europe and before returning to Edwards Air Force Base.

Two years later Enterprise returned and was placed in a storage hangar near Runway 12/30 to await construction of a planned expansion to the National Air and Space Museum.

[50] On June 1, 1985, New York Air began a small hub operation at Dulles, with 35 daily flights to eight cities in Florida and the northeastern United States.

[54] When the SR-71 was retired by the military in 1990, one was flown from its birthplace at United States Air Force Plant 42 in Palmdale, California, to Dulles, setting a coast-to-coast speed record at an average 2,124 mph (3,418 km/h); the trip took 64 minutes.

[56] The 2004 launch of low-cost carrier Independence Air propelled IAD from being the 24th-busiest airport in the United States to fourth, and one of the top 30 busiest in the world.

[9] On April 17, 2012, the Space Shuttle Discovery was ferried to Dulles mounted to a NASA 747-100 as part of its decommissioning and installation in the Steven F. Udvar-Hazy Center.

[59] A few weeks later, on June 1, the first passenger flight of the Boeing 747-8 Intercontinental – operated by Lufthansa with service from Frankfurt to Washington – landed at IAD.

[62] Less than two years later, on February 1, 2016, Emirates upgraded its direct flights from Dubai International – a service previously operated using a Boeing 777 – to an Airbus A380.

[citation needed] By 2019, Washington Dulles was one of just fourteen airports in the United States seeing daily operations from – and/or have at least one gate and one runway that can accommodate – an Airbus A380; the others being Atlanta, Boston, Chicago-O'Hare, Dallas/Fort Worth, Denver, Honolulu, Houston-Intercontinental, Las Vegas, Los Angeles–LAX, Miami, New York–JFK, Orlando and San Francisco.

[65] A few months later, on September 15, Cathay Pacific launched its longest nonstop route connecting Dulles to Hong Kong utilizing an Airbus A350-1000; the service was suspended indefinitely due to the COVID-19 pandemic.

[70] The airline announced it would operate flights between Dulles and small airports in Pennsylvania and West Virginia, some of them on Essential Air Service contracts.

The entire terminal complex has a total of 139 gates – 123 of which have jetways and 16 of which are hardstand locations[79] from which passengers can board or disembark using the airport's plane mate vehicles.

The main terminal was recognized by the American Institute of Architects in 1966 for its design concept; its roof is a suspended catenary providing a wide enclosed area unimpeded by any columns.

[85] A separate security checkpoint is available on the baggage claim level for staff only, and previously had access for all passengers as the Dulles Diamond area.

[90][91] The C/D concourses were given a facelift in 2006 that included light-fixture upgrades, new paint finishes, new ceiling grids and tiles, heating and air conditioning replacement, and complete restroom renovations.

As of November 1, 2008, MWAA assumed responsibility from the Virginia Department of Transportation both for operating the Dulles Toll Road and for the construction of the Silver Line down its median.

[195] Uber and Lyft are popular modes of transport to and from the airport, and MWAA receives a $4 fee per trip, which is included in the quoted fare.