There are 9 US Post Offices in Giles County serving a total of 17,999 residents equating to 2,000 residents per post office. It's estimated that approximately 28,728 packages are handled across the 9 county post offices annually. Giles County is a county located in the U.S. state of Virginia. As of the 2010 census, the population was 17,286. Its county seat is Pearisburg. Giles County is included in the Blacksburg-Christiansburg-Radford, VA Metropolitan Statistical Area. Giles County is the location of Mountain Lake, one of only two natural fresh water lakes in Virginia. The Lake drains into Little Stony Creek, which passes over \"The Cascades\", a spectacular waterfall, before reaching the New River."