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. Over two centuries or so, many other objects of greater or lesser permanence have been used. Benchmarks can be found at various locations all over the United States. They are used by land surveyors, builders and engineers, map makers, and other professionals who need an accurate answer to the question, "Where?"
In addition to logging this cache, as a bonus, the benchmark itself can also be logged. There are many different kinds of benchmarks, placed by a variety of different agencies. Some benchmarks in this series can be logged directly on the Geocaching.com website, others can be logged at waymarking.com.
This particular benchmark was placed at this location by the Indiana Department of Transportation several years ago when the bridge in which it is set was replaced. The coordinates for the cache should take you to both the cache and the benchmark. The benchmark can be logged by clicking on the following link WMGAFF Benchmark Link.
To successfully log the benchmark, you’ll need to take at least one picture of the benchmark, preferably two. The required photo must be a close up, the second, a more ‘distant’ photo that includes the mark. If it’s your first time visiting waymarking.com, you’ll have to register for an account on the site. To successfully log the cache, you must, of course, find the container and sign the log!
Be stealthy, but if anyone asks, you're there to check out the benchmark!