Harmony Hall is in the Broad Creek Historic District, the first historic district formed under Prince George's County preservation law. The house is an 18th century Georgian country house that architecturally ranks as one of the great early plantation houses and an outstanding early colonial house of Maryland. The front of the house faces the Potomac River and remains much as it appeared in 1766, the estimated time of construction.

The story of Thomas Stone is not just the story of man who signed the Declaration of Independence. It is about a peace loving man, who only after realizing he had no further options for peace, pledged his life, fortune, and sacred honor toward the vision of an independent America. It is about a devoted family man who took in six other family members upon the death of his father, and when his wife became gravely ill, put his national aspirations on hold to spend more time with her and their children. When you visit Thomas Stone National Historic Site, you are truly taking a step back in time. Whether it is the restored manor house, or the collection of 19th century outbuildings,or just the quiet and solitude, there is something for everyone here. Come spend some time here and learn of this hidden jewel in the national park system. Located in Charles County, Maryland, Thomas Stone NHS is 25 miles south of Washington D.C.