West Fayette County encompasses an extraordinary historic, scenic, and cultural American landscape in the National Register-listed West Fayette County Rural Historic District. Covering almost 4,000 acres, the district includes fifteen historic farms and Keeneland Race Course, which together tell the story of America's Thoroughbred industry from the early 1900s through World War II through the breeding, raising, training, and racing of Thoroughbreds during one of its most fascinating eras. Its historic resources include Thoroughbred farms established in the early 20th century, with buildings designed for specific functions and signature details. The district includes the world-renowned Calumet Farm and the full acreage of E.J.R. Bradley's Idle Hour Stock Farm, now comprising Darby Dan and other farms along both sides of Old Frankfort Pike. Together, these farms and spaces affirm the district's national significance, with historic resources representing exploration and settlement, agriculture, and domestic architecture from 1790 through 1940. The east boundary of the West Fayette Rural Historic District coincides with the west boundary of the Lexington-Fayette Urban Service Area, and the abrupt change at Alexandria Drive and Old Frankfort Pike from modern industrial development to rolling pastures marks this critical infrastructure, land use, and zoning line. Historic preservation and conservation easements on district farms form a strategic barrier against future development.