Description
- 1.75″ X 1.75″ metal magnet
Petrified Forest Museum Association
$5.99
U.S. Geological benchmarks are permanent survey markers (also known as geodetic control points) at known elevations and are used as reference points for other topographical measurements.
Benchmarking is a favorite activity of many park visitors in which they search for and record where they have found the USGS survey markers.
In stock
Dimensions | 2.5 × .25 × 5.0 in |
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