Most manor-style homes built since the Civil War were merely country retreats for wealthy industrialists in the late 19th and early 20th century and had little agricultural, administrative or political function. Examples of these homes include Castle Hill (Ipswich, Massachusetts), Vanderbilt Mansion National Historic Site and Hearst Castle. A rare example of hereditary estate ownership in the United States that includes a manor-type house is Gardiners Island, a private island that has been in the same family since the 17th century and contains a Georgian architecture house. Today, some historically and architecturally significant manor houses in the United States are museums. However, many still function as private residences, including many of the colonial-era manor houses found in Maryland and Virginia a few of which are still held within the original families.