BenchMarking

1. BenchMarking

2. What is a benchmark? A benchmark is a point whose position is known to a high degree of accuracy and is normally marked in some way. The marker is often a metal disk made for this purpose, but it can also be a church spire, a radio tower, a mark chiseled into stone, or a metal rod driven into the ground. Benchmarks can be found at various locations all over the United States.

3. They are used by land surveyors, builders and engineers, map makers, and other professionals who need an accurate answer to the question, "Where?" Many of these markers are part of the geodetic control network (technically known as the National Spatial Reference System, or NSRS) created and maintained by NOAA's National Geodetic Survey (NGS).

4. Why search for benchmarks? The interesting thing about benchmarks is that a majority of them are located in plain sight (though largely ignored by the general public). Searching out these locations and documenting them allows others to share pictures of the various areas where they are placed. Some of these points haven't been visited and documented in a very long time, so you may also be rediscovering long neglected objects of American history as well!

5. Finding a benchmark A GPSr makes getting to the right area easier, but when you're there, you will (generally) be better off if you use the details of the benchmark's location description to locate it. You can search for benchmarks using a zip code or coordinates on Geocaching.com

7. Some benchmark types include Vertical Control Marks, Horizontal Control Marks, Intersection Stations ,and Triangulation Stations To learn more about benchmarking, visit Geocaching.com