Warren County is a U.S. county located in the Commonwealth of Virginia. The 2020 census places Warren County within the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area with a population of 40,727. The county was established in 1836. The county seat is Front Royal.

The Washington metropolitan area, also referred to as the DC area, Greater Washington, the National Capital Region, or locally as the DMV, is the metropolitan area centered around Washington, D.C., the federal capital of the United States. The metropolitan area includes all of Washington, D.C. and parts of Maryland, Virginia, and West Virginia. It is part of the larger Washington–Baltimore combined statistical area, which is the third-largest combined statistical area in the country.