Augusta County is a county in the Shenandoah Valley on the western edge of the Commonwealth of Virginia in the United States. The second-largest county of Virginia by total area, it completely surrounds the independent cities of Staunton and Waynesboro. Its county seat is Staunton, but most of the administrative services have offices in neig…Augusta County is a county in the Shenandoah Valley on the western edge of the Commonwealth of Virginia in the United States. The second-largest county of Virginia by total area, it completely surrounds the independent cities of Staunton and Waynesboro. Its county seat is Staunton, but most of the administrative services have offices in neighboring Verona.