The architecture is distinctive for "its unusual pentastyle portico". It is suggested that Thomas Jefferson, his close friend, may well have drawn plans for Oak Hill; the construction was supervised by James Hoban, designer and builder of the White House. Aside from the main house, other structures remaining from Monroe's time include the cottage, a smokehouse, springhouse, blacksmith's shop, a square barn, the stone Stallion Barn, and possibly the Brick House. The estate is a designated U.S. National Historic Landmark.

Monroe and his uncle Joseph Jones jointly purchased 4,400 acres of land in Loudoun County in 1794. When Jones died without direct heirs in 1805, Monroe gained sole possession of the property. However, Monroe continued to live primarily at Highland, his residence in Albemarle County—until 1826, when he was forced to sell that property to pay debts he had incurred while serving as President.

LARRY PERSONAL NOTE: AFTER DETOURING NEARLY TWO-AND-A-HALF HOURS TO GET TO THIS PLACE IN HEAVY SLOW TRAFFIC, I LEARNED THE HOUSE IS PRIVATELY OWNED AND THE OWNERS DO NOT ALLOW PUBLIC TO EVEN SEE THE EXTERIOR OF THE HOUSE!