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Department Begins New Survey of Mason-Dixon Line

Effort To Document Remaining Original Markers

Photo of Maryland Geological Survey signThe Maryland Geological Survey, a unit of the Maryland Department of Natural Resources, will lead professional surveying societies of Maryland and Pennsylvania in a new survey of monuments along the Mason-Dixon Line. This will be the first complete survey in 40 years of the line, which was marked in a 1760s survey that defined the Maryland-Pennsylvania border. 

Surveyors will document and photograph the remaining monuments to create a thorough collection, with the intent of entering the markers into the National Registry of Historic Places. The project is slated to begin in February and continue through August 2021. 

Photo of marker along Mason-Dixon lineMaryland Geological Survey is working with the Commonwealth of Pennsylvania, Maryland Historical Trust, the Maryland Society of Surveyors, and the Pennsylvania Society of Land Surveyors on the effort. Fieldwork will be conducted by the two professional societies at no cost.

The department is also asking for the public’s help. People who own property within the survey zone are asked to allow access to the site —  all surveyors will have identification and documentation from the Department of Natural Resources. Also the surveyors would be interested to hear and document any stories people have about the monuments.