Greenway Court is a historic country estate near White Post in rural Clarke County, Virginia. The property is the site of the seat of the vast 18th-century land empire of Thomas Fairfax, 6th Lord Fairfax of Cameron (1693–1781), the only ennobled British colonial proprietor to live in one of the North American colonies. The surviving remnants of his complex — a later replacement brick house and Fairfax's stone land office — were designated a National Historic Landmark in 1960.

Clarke County is a county in the Commonwealth of Virginia. As of the 2020 census, the population was 14,783. Its county seat is Berryville. Clarke County is included in the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area.