Arlington County, Virginia area. The county is situated in Northern Virginia on the southwestern bank of the Potomac River directly across from Washington, D.C., of which it was once a part. With a land area of , Arlington is the geographically smallest self-governing county in the U.S., and by reason of state law regarding population density, has no incorporated towns within its borders. Due to the county's proximity to downtown Washington, D.C., Arlington is home to many important installations for the capital region and U.S. government, including the Pentagon, Reagan National Airport, and Arlington National Cemetery. Many schools and universities have campuses in
Streets and highways of Arlington County, Virginia Streets and highways of Arlington County, Virginia This article deals with the streets and highways of Arlington County, Virginia, a suburb of Washington, D.C. in the United States. In 2009, the county maintains of roads. , the total mileage of (primary) state highways in Arlington County was 39.66 (59 km). Arlington County is one of only two counties in Virginia which maintain its own roads (with the exception of primary state highways, including U.S. Highways and Interstates), the other being Henrico County outside the State Capital of Richmond. Because of this special status, there are no secondary state roads and,