National Landing is an area in Northern Virginia encompassing parts of the Crystal City and Pentagon City neighborhoods of Arlington County and the Potomac Yard neighborhood in the city of Alexandria. It is the location of the Amazon HQ2 headquarters. The neighborhood was branded and announced as "National Landing" in 2018 as a part of local economic development plans to bring Amazon HQ2 to the area. The announcement also included plans to build a graduate-school satellite university campus of Virginia Tech in the area. The "National Landing" name derives, in part, from the area's proximity to Ronald Reagan Washington National Airport.

Crystal City is an urban neighborhood in the southeastern corner of Arlington County, Virginia, south of Downtown Washington, D.C. Due to its extensive integration of office buildings and residential high-rise buildings using underground corridors, travel between stores, offices, and residences, it is possible to travel much of the neighborhood without going above ground, making at least part of Crystal City an underground city.