Mason-Dixon Survey
Philadelphia, Philadelphia County, Pennsylvania
Marker Inscription
Here, in 1763, the southernmost point of Philadelphia was determined as the starting point for the survey of one of the most important borders in the nation. Charles Mason and Jeremiah Dixon took scientific measurements of a degree of latitude, elevating professional surveying standards. The survey ended a land dispute begun by William Penn and Lord Baltimore. Western Pa. Indian wars and severe weather delayed completion of the line until 1768.
Erected by Pennsylvania Historical and Museum Commission
The Story
In 1763, English astronomers Charles Mason and Jeremiah Dixon set their instruments near Philadelphia's southernmost point to settle one of colonial America's most stubborn quarrels — a boundary dispute between the Penn and Calvert families that had simmered for generations. Their painstaking measurements of a degree of latitude set a new standard for professional surveying, though Indian conflicts and harsh weather to the west delayed the line's completion until 1768. The border they traced would one day take on a meaning far beyond property: the symbolic divide between North and South.
Why it matters
The Mason-Dixon Line began as a colonial land settlement but became the nation's most famous cultural boundary, marking the edge between free and slave states in the decades before the Civil War.
Plan your visit
NearbyMake a day of it — museums, food, and places to stay near this marker.
Museums & culture
- Thaddeus Kosciuszko National Memorial0.3 mi away
- Hill-Physick House0.3 mi away · 321 South 4th Street
- Powel House0.4 mi away · 244 South 3rd Street
- Merchants' Exchange Building0.5 mi away · 143 South 3rd Street, Philadelphia, PA
- Independence Living History Center0.5 mi away
- Museum of the American Revolution0.5 mi away · 101 South 3rd Street, Philadelphia, PA
Attractions
- USS Becuna0.2 mi away · South Christopher Columbus Boulevard, Philadelphia, PA
- USS Olympia0.2 mi away · South Christopher Columbus Boulevard, Philadelphia, PA
- City Tavern0.4 mi away · 138 South 2nd Street
- First Bank of the United States0.5 mi away · 120 South 3rd Street, Philadelphia, PA
- Carpenters' Hall0.5 mi away · 320 Chestnut Street, Philadelphia, PA
- USS New Jersey0.6 mi away · Wiggins Promenade, Camden, NJ
Food & drink
- FRIEDA0.5 mi away · 320 Walnut Street, Philadelphia, PA
- Olivier Cafe0.6 mi away · 50 South 3rd Street, Philadelphia, PA
- Buddakan0.6 mi away · 325 Chestnut Street, Philadelphia, PA
- Franklin Social0.6 mi away · 401 Chestnut Street, Philadelphia, PA
- National Mechanics0.6 mi away · 22 South 3rd Street, Philadelphia
- Menagerie Coffee0.6 mi away · 18 South 3rd Street, Philadelphia, PA
Places to stay
- Hilton Philadelphia at Penn's Landing0.3 mi away · 201 South Christopher Columbus Boulevard, Philadelphia, PA
- Philadelphia Marriott Old City0.4 mi away · 1 Dock Street, Philadelphia, PA
- Thomas Bond House0.5 mi away · 129 South 2nd Street, Philadelphia
- Apple Hostels Philadelphia0.6 mi away · 32 South Bank Street, Philadelphia, PA
- Best Western Plus Independence Park Hotel0.6 mi away · 237 Chestnut Street, Philadelphia, PA
- Apple Hostels0.6 mi away · 33 Bank Street, Philadelphia, PA
Places data © OpenStreetMap contributors. Hours and details change — call ahead.
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Related people
- · Charles Mason
- · Jeremiah Dixon
- · William Penn
- · Lord Baltimore
Themes & tags
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