Crystal City, Arlington, Virginia Crystal City, Arlington, Virginia 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 is possible without going above ground; thus, a large part of Crystal City is an underground city. Crystal City includes offices of numerous defense contractors, the United States Department of Labor, the United States Marshals Service and many satellite offices for The Pentagon. It is also the location of Ronald Reagan Washington National Airport. Crystal City
Organizational structure of the United States Department of Defense Organizational structure of the United States Department of Defense The United States Department of Defense (DoD) has a complex organizational structure. It includes the Army, Navy (the Marine Corps is a subset of the Navy), Air Force, the Unified combatant commands, U.S. elements of multinational commands (such as NATO and NORAD), as well as non-combat agencies such as the Defense Intelligence Agency and the National Security Agency. The DoD's annual budget was roughly US$496.1 billion in 2015. This figure is the base amount and does not include the $64.3 billion spent on "War/Non-War Supplementals". Including those items brings the total