The Isaac Royall House is a historic house located at 15 George Street, Medford, Massachusetts. It is a National Historic Landmark, operated as a non-profit museum, Governor John Winthrop built a house on the site about 1637. Around 1692, that house was replaced with a more imposing brick structure standing 2½ stories high and one room in depth, with exceedingly thick walls. On December 26, 1732, Isaac Royall, Sr., a slave trader, rum distiller, and wealthy merchant of Antigua, purchased the house and 504 acres of land along the west bank of the Mystic River in what was then Charlestown, an area annexed to Medford in 1754. He remodeled the house extensively between 1733 and 1737, adding a third story, encasing the east facade in clapboard, and ornamenting the exterior with architectural details and continuous strips of spandrel panels. Royall also constructed outbuildings in 1732, including the only known slave quarters that survive in New England. After this construction, Royall brought 27 enslaved Africans from Antigua, which doubled the enslaved population of the community. Wikipedia