Arlington, Virginia: Location and Significance

Arlington County lies in northern Virginia, directly across the Potomac River from Washington, D.C. It's part of the D.C. metropolitan area, bordered by Alexandria (south) and Fairfax County (west/north).

Key landmark: The Pentagon—U.S. Department of Defense headquarters—making Arlington a national security hub. It also hosts Arlington National Cemetery, Reagan National Airport, and dense urban corridors like Rosslyn and Crystal City.