Rock Spring Farm is located in the southwestern outskirts of Leesburg, in the town’s local Old & Historic District. The original brick house at Rock Spring Farm was completed around 1826 for John Gill Watt. The Loudoun County property at one time was known as Rosemont, but was renamed Rock Spring Farm in the 1840s in recognition of the springs on the estate that supplied water to the town of Leesburg for more than 200 years. Throughout most of the 19th century, Rock Spring Farm was owned and occupied by Henry Saunders, a veteran of the War of 1812. Under the ownership of the prominent Harrison family after 1899, the dwelling was enlarged and high-style ornamentation of the popular Colonial Revival style was applied. The five-acre property includes a springhouse, dairy, silo, barn, smokehouse, and several other farm outbuildings.