Located south of Laurel in Prince George's County, Maryland, United States, Montpelier Mansion is a five-part, Georgian style home most likely constructed between 1781 and 1785. It has also been known as the Snowden-Long House, New Birmingham, or simply Montpelier. Built by Major Thomas Snowden and his wife Anne, the house is now a National Historic Landmark operated as a house museum. The home and 70 acres (28 ha) remain of what was once a slave plantation of about 9,000 acres (3,600 ha).
It was declared a National Historic Landmark in 1970.(Wikipedia)