The Tannery (aka The Nicholas Holtz House or the "Mansion House") is a late eighteenth century residence (c. 1790) illustrating fine federal architectural detailing and brickwork. Although research on the house is not yet complete, according to Williams' History of Frederick County, "on this farm one of the first tanneries in Frederick County was started by Major Holtz... The dwelling house on this farm is one of the oldest in that part of Frederick County, the bricks being hauled from Baltimore in four horse wagons."
The Tannery stayed in the Holtz family until 1948. In 1980 it began its transformation.