Part of a land grant of 1670, the plantation on which this venerable colonial manor house is located originally was called Bowling Green after the green sward before the entrance. The name was changed to Old Mansion when its owner, Maj. John Hoomes, donated property for the Caroline County courthouse and permitted the newly formed county seat to take the name of his estate. The house, with its fine brickwork, hipped dormers, original sash, jerkinhead roof, and interior paneling, was constructed in 1741, and it preserves a romantic image of a prosperous colonial Virginia plantation seat. A later gambrel-roofed rear wing adds to its interest. The cedar-lined lawn stretching from the front is the remnant of a colonial race track. South of the house are the earth terraces of a large early garden. George Washington and his troops camped on the property during the Revolutionary War.  Old Mansion is a contributing property in the Bowling Green Historic District.