the National Geodetic Survey periodically has to recalculate the location of all its markers. In 2012, it completed a recalculation of 80,000 markers nationwide. Many of the concrete monuments ...

The map directed him to a place where he found not a marker, but a square hole in the ground. Someone had removed the 4-foot concrete shaft. That sort of thing drives surveyors mad. They want ...

Forty surveyors signed up for the project ... "We have 24 of the mounds that we are absolutely certain of, and we put concrete markers on them," Denny said. "We have 10 locations that, because ...

a Gettysburg surveyor and the Pennsylvania director of the volunteer project. Some markers were moved in the early 1900s and set in new concrete — but not always exactly along the border ...

a Gettysburg surveyor and the Pennsylvania director of the volunteer project. Some markers were moved in the early 1900s and set in new concrete – but not always exactly along the border ...

The stones had been leaning, were settling or had been broken. Surveyors removed the markers, dug a hole, poured concrete and reset the stones. While the crown stone at Mile 40 was located ...

“I thought that would give me some historical reference,” Robert said of the concrete post ... They aren’t U.S. Geological Survey geodetic markers. Those have a distinctive metal disk ...

Survey monuments are mostly 3-inch cast metal disks affixed to the tops of pipes that have been pounded into the ground or fastened on large rocks or concrete pillars. A legend is usually stamped ...

At the time, surveyor Michael McGee predicted that the small brass disk — attached to the concrete with heavy-duty glue — would suffer the fate of similar markers and be stolen by vandals.