They are tiny, measuring between 8 and 10 centimeters. They are bronze. No one knows for sure how many there are, but the number may exceed one million. You will find them from sea to shining sea, including Alaska and Hawaii. They are placed into city sidewalks and hammered into remote mountain tops. Simply put, these little markers are part of a leveling network to precisely measure elevation. But first, a little history...
In 1807, President Jefferson established the Survey Of The Coast, the government agency responsible for surveying the ever-expanding American interior. In 1878 it reorganized into the Coast & Geodetic Survey. Over the decades the name and bureau continued to evolve, then in 1970, the National Geodetic Survey became part of the NOAA (National Oceanic & Atmospheric Administration) within the United States Department of Interior. Set by surveyors and mapmakers, not only do they measure elevation, but they can be part of a triangulation network and form the basis of control for topographical maps.
Local governments often control the setting of the ones found in urban areas. The ones most interesting to outdoor enthusiasts are off the beaten trail and have generally been set by the US Geological Survey, The Forest Service or Corp of Engineers. These benchmarks usually include a small triangle and the elevation, and are dated and stamped. Many are accurate to as far as 100 feet, while others can be a few thousand feet from the mark they refer to (such as a pinnacle, rendering them nearly impossible to find). The older ones are hammered or cemented in, new ones are often epoxied in. Not surprisingly, over the years construction has destroyed many and vegetative growth has buried others. No doubt, eons from now some will be rediscovered. We can't help but wonder what kind of buzz that will generate!
Benchmarking, the hunt and documentation of these markers, is hobby similar to geocaching. While we don't trek with the goal of benchmarking, we do enjoy finding them when we are hiking. And documenting them on social media pages has become a thing. The National Geodetic Survey maintains a large database of them. Over the last several years, National Park Service bookstores sell local park replicas, which make good little momentos.
These are important land markers, and each has its own history. Please never alter or change them in any way. It's usually not possible to move them, but even if possible, never do so.
Many are quite easy to find, but we swear others seem purposefully hidden (that can actually be half the fun of finding them). The older and exposed ones are often severely weathered by time and nature. Many are accurate to as far as 100 feet, while others can be a few thousand feet from the mark they refer to (such as a pinnacle, rendering them nearly impossible to find). The next time you are hiking, keep your eyes open for them. When you are lucky enough to find one, take a pic and post it online.
