Carroll County is a United States county located in the southwestern part of the Commonwealth of Virginia. Roughly one fifth of the county lies in the Virginia Piedmont region, while the rest is part of the Appalachian Mountains. The Carroll county seat and largest town is Hillsville.
The county was established in 1842 from part of Grayson County, and was officially named in honor of Charles Carroll, a signer of the Declaration of Independence. The borders of Carroll County were later expanded by including land from Patrick County.
The total size of the county is 478 square miles (1,238 km2), and, as of the 2010 census, the population was 30,042. Carroll, along with other Appalachian counties, is among the poorest parts of Virginia.