(WHTM) — From 1763 to 1767, Charles Mason and Jeremiah Dixon surveyed the boundary between Pennsylvania and Maryland.

Says Eric Gladhill, member of the Pennsylvania Society of Land Surveyors, “It was probably the most important survey of the colonial states, because of a land dispute between Lord Calvert and William Penn’s descendants.”

The charters of the two colonies overlap and some four thousand square miles of territory are in dispute. It takes decades, and a few unpleasant exchanges of lead projectiles, before the two sides negotiate a line Mason and Dixon will set in stone, literally.

As they push along the new line, they place a simple marker stone, with “M” on one side and “P” on the other, at every mile. Every five miles they erect a more elaborate marker called a crown stone, with the seal of the Penn family of Pennsylvania on one side, and the seal of the Calverts of Maryland on the other. Ultimately they would place 133 stones.

Now a new effort is underway to document the markers. The project is coordinated by the Maryland Geological Survey. The ultimate goal, get the markers on the National Register of Historic Places.

“They feel that it will help them to garner some grant money to help maintain it,” Gladhill said.

There’s already a great deal of documentation of the markers, thanks to previous surveys. But to get on the National Register of Historic Places, people need to visit the stones, confirm and update the information, and take pictures. With a limited budget, MGS called for volunteers to be the boots on the ground.

“They asked the Maryland Society of Surveyors, and they, in turn, asked the Pennsylvania Society of Land Surveyors, which I’m a part of both organizations, so I got involved with it,” Gladhill said.

The survey kicked off in March of 2020.

“And then of course the Covid Pandemic hit,” Gladhill said. “And things grinded to a halt rather quickly.”

They hoped to wrap things up by August 2021. Now it will have to go into 2022, but it can’t go too far into 2022.

“The National Registry of Historic Places requires that all the data be gathered in a two-year period,” Gladhill said. “The deadline would be March of 2022, and I know there have been some inquires about whether they would extend it because of the COVID pandemic, but I haven’t heard any response to that.”

Work has slowed in recent months, but COVID isn’t the main cause. You’d think summer would be the ideal time to go out marker hunting, but Gladhill says that’s not the case. Both undergrowth and overgrowth can get in the way.

“The bees and bears, snakes, and so forth are an issue.” (Gladhill has been stung by bees more than a few times.) “Also the leaf canopy on the trees makes it difficult to get a GPS signal, If you want to get accurate surveying coordinates.”

Gladhill is hoping volunteering for the project will pick up when the leaves fall.

Thanks to GPS positioning technology, instead of dragging out the full bulky, heavy kit of surveying gear, most of the work can be done with a cell phone equipped with a surveying app. First, though, you have to get to the marker. Some are near roads, and easy to access, but often the stones are on private property, or out in the woods and wilds, and require long hikes to reach. The condition of the stones varies widely.

“In many cases, they’re almost pristine,” Gladhill said. “In some cases, they look very distinct, the carvings are clear, you can still see the fluting on the edges that the stonemasons did.”

Other stones are in dreadful shape, and More often than not, humans do the damage.

“Hit by plows, vandalized, broken off for souvenirs, some places they were just in the way and people took machinery and tried to break them off,” Gladhill said. “Hunters use them for target practice.”

The one thing the project needs to cross the March 2022 finish line is volunteers. The good news, you don’t have to be a surveyor to help.

Gladhill says “Anyone who’s interested and can operate an Esri program, Esri is a brand of GIS, or Geographic Information System, anyone who can operate a smartphone and can navigate and find a stone is welcome to sign up and do some of this volunteer work.”

Gladhill says preserving the stones is important and not just because of the history.

“Where the original monument sets overrules everything else regardless of what the measurements say, what the deed says, the placement of the original monument has been found by the courts to be the official boundary.”

To get more information about volunteering, click here.