The complex of structures that make up The Mill House property, located in Fauquier County’s Cromwell’s Run Rural Historic District, reflects an early gristmill operation and the area’s 20th-century hunt-country society. A mill was operated here by Charles Chinn as early as 1768. Leven Powell, founder of the nearby town of Middleburg, was responsible for many of the present buildings, including the mill, the miller’s house, the cooper’s house, a dairy-smokehouse, and the mill owner’s house (now the centerpiece of the complex). After the mill ceased operation, the Fauquier County property took on an entirely new aspect with its purchase by John S. Phipps, son of Henry Phipps, a partner of Andrew Carnegie and founder of the United States Steel Corporation. From 1924 to 1929 Phipps enlarged the house, converted several outbuildings to guest quarters, added a stable and swimming pool, and united the complex with landscaping. Though today a splendid country estate, the rustic character of The Mill House property has been maintained.