Northern Virginia from the older National Airport (a focus city for American Airlines) are restricted for distance, frequency, and flight paths due to the proximity to federal facilities, Dulles is the region's second busiest airport in both passenger loadings and aircraft movements, and the sixteenth-busiest airport in the United States by takeoffs and landings in 2007. Dulles is the region's primary international gateway, serves as a hub for United Airlines, and has recently improved its low-cost carrier offerings with the addition of multiple flights by Southwest and JetBlue. Commuters are served by the Washington Metro subway and the Virginia Railway Express, a
Dulles District Dulles District The 4A Dulles District is a high school conference in the state of Virginia that includes schools from Northern Virginia, with all of its full-time members from Loudoun County. 4A is the third largest enrollment class of the Virginia High School League and is typically very competitive in Virginia high school sports. The Dulles District schools compete in the 4A West Region with the schools from Conference 21A, Conference 22, Conference 23, and Conference 24. The Dulles District was created in 2001 from all six Loudoun County high schools that were in the AA Northwestern District, which were