Arlington, Northampton County, Virginia]Arlington County is a county in the Commonwealth of Virginia. As of 2010, it has a population of 207,627 residents. It is located directly across the Potomac River from Washington, D.C., and the two of them are linked by several highway and railroad bridges. A major airport of Washington, D.C., Ronald Reagan Washington National Airport, many Federal Government offices, including those of the Department of Defense, the Department of the Navy, the Drug Enforcement Agency, Arlington National Cemetery, and DARPA are located in Arlington County.The county was originally founded as Alexandria County on February 27, 1801 by passage of the District of Columbia Organic Act of 1801. Alexandria County along with the now-defunct Washington County were the two counties formed on that date within the District of Columbia. Due to issues involving congressional representation, abolition and economic decline, the county along with the then-Town of Alexandria were returned to the Commonwealth of Virginia in an act of the U.S. Congress which took effect in 1847. In 1920 the General Assembly of Virginia changed the name of the county to "Arlington County" in order to avoid confusion with Alexandria, which had become an independent city in 1870.Arlington County is organized legally as one of the counties of Virginia. For purely statistical considerations, it is included with the nearby cities and counties as a city of the Washington Metropolitan Area by the U.S. Census Bureau. With a land area of 26 sqmi, Arlington County is geographically the smallest self-governing county in the United States.In 2002, Arlington received the EPA's National Award for Smart Growth Achievement for "Overall Excellence in Smart Growth." In 2005, Arlington was ranked first among walkable cities in the United States by the American Podiatric Medical Association. CNN Money ranked Arlington as the most educated city in 2006 with 35.7% of residents having held graduate degrees. Along with five other counties in Northern Virginia, Arlington ranked among the twenty American counties with the highest median household income in 2006. In October 2008, BusinessWeek ranked Arlington as the safest city in which to weather a recession, with a 49.4% share of jobs in "strong industries". In July 2009, CNN Money ranked Arlington second in the country in its listing of "Best Places for the Rich and Single." In June 2010, Parenting magazine named Arlington as the "Best City for Families" in the country.Arlington is the location of the Arlington National Cemetery, the Ronald Reagan Washington National Airport, The Pentagon (of the U.S. Department of Defense), Fort Myer (of the U.S. Army), the Pentagon Memorial, the U.S. Marine Corps Memorial, and the U.S. Air Force Memorial.