From Southern Maryland Wiki @ somd.com
Upper Marlboro, was built circa 1704 and served as the residence of notable Marylanders Colonel Henry Darnall and his great-grandsons, Archbishop John Carroll and Daniel Carroll II. The home was remodeled in 1858, and restored in 1988. An unusual 18th century burial vault is located on the grounds. This 1.5-story historic house is listed on the National Register of Historic Places. The facility is open to the public by appointment, and walk-in tours are available. Additionally, the building (with a capacity of 100) and grounds are available for rentals for weddings, receptions, meetings, and other business and social events. Please call for an appointment and/or additional information about tours, rental opportunities, and fees.