Alleghany County is an American county located on the far western edge of Commonwealth of Virginia. It is bordered by the Allegheny Mountains, from which the county derives its name, and it is the northernmost part of the Roanoke Region. The county seat is Covington. As of the 2020 census, the population was 15,223.

A county seat is an administrative center, seat of government, or capital city of a county or civil parish. The term is in use in five countries: Canada, China, Hungary, Romania, and the United States. An equivalent term, shire town, is used in the U.S. state of Vermont and in several other English-speaking jurisdictions. County towns usually serve a similar function in Ireland, Jamaica, and the United Kingdom.