Throughout much of the 17th and 18th centuries, the land around what is now the Zimmerman Center for Heritage stood at the center of a long border dispute between Maryland and Pennsylvania. In 1632, King Charles I granted the second Lord Baltimore a charter for Maryland with its upper boundary at the 40th parallel, about two miles north of here, but when William Penn received a charter for Pennsylvania from King Charles II in 1681 and founded Philadelphia south of that line, the lack of a natural boundary made the competing claims difficult to define. Thomas Cresap, born in Yorkshire, England about 1694, immigrated to Maryland in 1718, married Hannah Johnson in 1727, and after living near the Susquehanna River, a brief stay in Virginia, and two years operating a ferry, acquired 150 acres on the river's west shore in 1729 in an area claimed by Pennsylvania and moved his family there in 1730. This tract, called Pleasant Garden and including the present-day Zimmerman Center site, was purchased from Stephen Onion through the Proprietary of Maryland. Cresap established Blew Rock Ferry there in competition with John Wright's ferry to the north and became notorious in the Susquehanna Valley for his role in the boundary dispute, as his hostile actions helped ignite bitter and violent conflict between the two colonies. For six years he clashed with local residents and law enforcement authorities and gained the nickname "The Maryland Monster." In November 1736, after a violent skirmish at his Pleasant Garden fort, he was captured, taken to Philadelphia, and imprisoned, reportedly telling his captors on entering the city, "Damn it…this is one of the prettiest towns in Maryland." After King George II intervened in 1737, Cresap was released and briefly returned to his home and family on the Susquehanna before moving to western Maryland near Oldtown, where he resumed his land and business pursuits and lived until 1790. Physical hostilities in the border conflict ceased in 1737 when King George II ordered both colonial governments to refrain from further conflict, but the dispute itself was not settled until 1750, when Britain's High Court of Chancery decided in favor of Pennsylvania. Charles Mason and Jeremiah Dixon then surveyed Pennsylvania's border with Delaware, Maryland, and Virginia from 1763 to 1767, though opposition by Native Indians delayed final resolution until 1784. The resulting boundary, about 15 miles south of here, ran 244 miles west from the Delaware River, became known as the Mason-Dixon Line, and later came to symbolize the border between North and South and between free states and slave states. Thomas Cresap has since been memorialized in both Maryland and Pennsylvania, where later generations honored him very differently from the hostile reputation he earned in Pennsylvania during the border war.