George Mason built a house named Hollin Hall after a family home in Yorkshire, England, for his son Thomson, in 1791. That house was destroyed by fire in 1827. In 1852, Thomson Mason’s property was purchased by Edward Curtis Gibbs. The estate passed through several owners before its purchase in 1913 by  Harley Wilson, who was a director at the North American Company. Mr. and Mrs. Harley Wilson completed Hollin Hall, a colonial revival mansion that was the centerpiece for their 600 acre estate near the Potomac River, in 1919.

Mrs. Wilson’s special love was gardening. She designed her own winding brick paths, walled gardens and flower beds. She added English boxwood obtained from England.

After Harley Wilson’s death in 1934, the estate was put up for sale. A Franklin D. Roosevelt advisor, Merle Thorpe bought the house and 89 acres. In 1959, Mount Vernon Unitarian Church purchased Hollin Hall and 10.34 acres.