Mason-Dixon Line
Carroll County, York County, Maryland
Marker Inscription
The historic boundary between Pennsylvania and Maryland was surveyed, 1763-1767, by Charles Mason and Jeremiah Dixon to settle border disputes between the two Provinces. This section of the Mason-Dixon Line was surveyed in late July and early August, 1765.
Erected by Pennsylvania Historical and Museum Commission
The Story
Between 1763 and 1767, English astronomers Charles Mason and Jeremiah Dixon surveyed the disputed boundary between Pennsylvania and Maryland, using precise celestial observations to settle a long-running colonial quarrel. This particular stretch was run in late July and early August of 1765. Their meticulous line became one of the most famous borders in America.
Why it matters
The Mason-Dixon Line resolved a bitter colonial land dispute and later came to symbolize the divide between North and South, making it one of the most storied boundaries in the nation's history.
Plan your visit
NearbyMake a day of it — museums, food, and places to stay near this marker.
Museums & culture
- Hanover Fire Museum6.3 mi away
- Neas House6.7 mi away · 103 West Chestnut Street, Hanover, PA
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Related people
- · Charles Mason
- · Jeremiah Dixon
Themes & tags
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