The Mason-Dixon Survey at 250 Years: Recent Investigations


The year 2013 marked the 250th anniversary of the 1763 start to the iconic land survey by Jeremiah Dixon and Charles Mason. This survey culminated in the border along the southern edge of Pennsylvania, now known as the Mason-Dixon Line. There has been little to report in the way of new information about the Mason-Dixon Survey—that is, until recently, when the exact location of the frst survey point was re-established. Research involving the original 1700s property deeds, insurance surveys, journal entries by Charles Mason, and City of Philadelphia Commissioners Reports, along with modern re-surveying of the area by professional surveyors, mathematical calculations by these same surveyors, and global positioning satellite (GPS) technology, combined to allow the recovery of the frst survey point calculated by Mason and Dixon. It was from this point that they proceeded to establish the Mason-Dixon Survey.