Hagerstown anchors the Hagerstown-Martinsburg, MD-WV Metropolitan Statistical Area, which lies just northwest of the Washington-Baltimore-Northern Virginia, DC-MD-VA-WV Combined Statistical Area in the Great Appalachian Valley. The population of the metropolitan area in 2000 was 222,771 and the 2008 estimate is 263,753 (U.S. Rank 169). It is the fastest growing metro area in the State of Maryland and among the fastest growing in the United States. 