Survey marker

Survey markers are world objects

Background
Permanent and embedded disks placed to mark key survey points, placed before the Great War by the United States Geological Survey. The markers were used in geodetic and land surveying.

The rock where the survey marker at Spruce Knob is located was removed from its original spot, which overlooked Spruce Knob Lake, and tossed nearby during the construction of Foundation.

Characteristics
Informally referred to as benchmarks, these landmarks indicate elevation in feet above sea level as well as contain horizontal position markers used for triangulation. Several points in Appalachia have markers placed, each labeled with a name, unique number, and instructions to contact the director of the agency in Washington, D.C. for more information.

Behind the scenes

 * The survey markers in were created by world artist John Valenti.
 * The benchmarks are based on real world survey markers, part of a national database maintained by the National Geodetic Survey (NGS), successor agency to the U.S. Coast and Geodetic Survey (USCGS).