There are 32 US Post Offices in Mcdowell County serving a total of 21,359 residents equating to 667 residents per post office. It's estimated that approximately 34,091 packages are handled across the 32 county post offices annually. McDowell County is a county in the U.S. state of West Virginia. As of the 2010 census, the population was 22,113. Its county seat is Welch. McDowell county is the southernmost county in the state. It was created in 1858 by the Virginia General Assembly and named for Virginia Governor James McDowell. It became a part of West Virginia in 1863, when several counties seceded from the state of Virginia during the American Civil War. McDowell County was also home of the famous Rocket Boys, who were from Coalwood."