Organizational structure of the United States Department of Defense of the Treasury. According to the U.S. Code, the Coast Guard is at all times considered one of the five armed services of the United States. During times of declared war (or by Congressional direction), the Coast Guard operates as a part of the Navy; this has not happened since World War II, but members have served in undeclared wars and conflicts since then while the service remained in its peacetime department. The Pentagon, in Arlington County, Virginia, across the Potomac River from Washington, D.C., is the Department's headquarters. The Department is protected by the Pentagon Force Protection Agency, which
Arlington County, Virginia the vast majority originating from Washington Metro stations. Arlington is served by the Orange, Blue, Yellow, and Silver lines of the Washington Metro. The Metro stations in Arlington are the only stations outside of Washington, D.C. where the system's original Brutalist architecture can be found. Additionally, Arlington is served by Virginia Railway Express commuter rail, Metrobus (regional public bus), Fairfax Connector (regional public bus), Potomac and Rappahannock Transportation Commission (PRTC) (regional public bus), (DASH bus) (regional public bus) and a county public bus system, Arlington Transit (ART). Metroway, the first bus rapid transit (BRT) in the D.C. area, is a