Our region has three major airports, and they’re all constantly changing. Here’s a look at how they’ve evolved over the past 30 years.

A US Airways diagram of National showing the Interim Terminal, which handled passengers during construction of terminal B/C, in the mid-1990s.

Ronald Reagan Washington National airport is both the region’s oldest and the one that’s closest to the District. American Airlines operated the first commercial flight there in 1941, and Eastern Air Lines was National’s dominant carrier until the beginning of the 1990s. It was only then that US Airways, an American subsidiary then called USAir, became the largest airline at the airport.

Northwest Airlines briefly operated a focus city at National after acquiring some of Eastern’s slots in 1991. It shrank the operation barely a year later in July 1992. Northwest merged with Delta Air Lines in 2009.

Northwest used gates in the Main Terminal (now terminal A) at National in 1992.

US Airways has operated out of the center and north piers of terminal B/C since it opened in July 1997.

US Airways’ facilities in terminal B/C, then the North Terminal, in September 1997.

As this current diagram shows, National hasn’t changed much since 1997.

The combined American-US Airways continue to use the center and north piers at National. Image from American Airlines.

BWI

The region’s busiest airport, Baltimore/Washington International (BWI), was also the first to sport a major airline hub when Piedmont Airlines made it its mid-Atlantic base in 1983.

BWI became a major hub for US Airways after its merger with Piedmont in 1989.

US Airways’ facilities in concourse D at BWI in 1990. Many of the former USAir Express gates are walled off today.

US Airways maintained its hub at the airport through the 1990s, only to close it in the early 2000s when Southwest emerged as the dominant airline at BWI.

A contemporary diagram of Southwest’s facilities at BWI. Image from Southwest Airlines.

Dulles

Washington Dulles International airport has seen the most growth in its facilities since the 1980s. New York Air built what became today’s Z gates when it established the first hub at Dulles in 1985. Continental Airlines acquired the hub when the airlines merged in 1987.

A Continental diagram showing the former New York Air terminal gates at Dulles in 1987.

United Airlines soon replaced Continental as the dominant carrier at Dulles, making the airport its primary east coast hub and transatlantic gateway in the late 1980s. It built concourse C, which first opened in 1986, and acquired space in concourse D from Continental in 1988.

A United map of Dulles showing the terminal gates, then new concourse B and the midfield concourses C and D in 1998.

Concourse A, including the regional gates used by some United Express flights, opened in 1999.

United’s facilities, including the regional concourse, at Dulles in 2002.

The Washington region’s airports continue to evolve. MWAA is designing a regional concourse at Reagan National, BWI is expanding its international facilities by connecting concourses D and E, and the long-awaited Metro station at Dulles is scheduled to open in 2018.