The Parkersburg–Marietta–Vienna Metropolitan Statistical Area, as defined by the United States Census Bureau, is an area consisting of three counties in West Virginia and one in Ohio, anchored by the cities of Parkersburg, West Virginia, Marietta, Ohio, and Vienna, West Virginia. As of the 2000 census, the MSA had a population of 164,264 (though a July 1, 2009 estimate placed the population at 160,905).