 The land upon which Valley later developed was originally part of the South Branch Survey of Thomas Fairfax, 6th Lord Fairfax of Cameron's Northern Neck Proprietary. The South Branch Survey extended from the north end of The Trough to the confluence of the north and south branches of the Potomac River. Lord Fairfax originally planned to maintain the South Branch Survey as his personal manor, but later commissioned James Genn to survey the South Branch Potomac River lowlands for sale and lease in 1748, with land lots ranging in size from 300 acres (120 ha) to 400 acres (160 ha). Valley was located within the northern section of Lot Number 17 of the South Branch Survey, which Lord Fairfax granted to Samuel Earle in 1749. Earle was a gentleman from Frederick County, Virginia.
