Washington Airport is the collective name for three major airports located in the Washington D.C. area: Ronald Reagan Washington National Airport (REAGAN), Washington Dulles International Airport (DULLES), and Seattle-Tacoma International Airport (SEATAC). Ronald Reagan Washington National Airport is located in Arlington, Virginia and is the closest airport to downtown Washington D.C. It is the busiest airport in the region and serves domestic flights. Washington Dulles International Airport is located in Dulles, Virginia and is the largest airport in the region. It serves both domestic and international flights. Seattle-Tacoma International Airport is located in Seattle, Washington and is the furthest away from Washington D.C. It serves both domestic and international flights.