Benchmarking, also known as benchmark hunting, is a hobby activity in which participants find benchmarks. The term "benchmark" is used only to refer to survey markers that designate a certain elevation, but hobbyists often use the term benchmarks to include triangulation stations or other reference marks. Like geocaching, the activity has become popular since 1995, propelled by the availability of online data on the location of survey marks and by the rise of hobbyist-oriented websites.
A person taking a photo of a located benchmark
A typical USCGS Benchmark
Typical metal rod or stake benchmark, in Texas
Benchmark in Saint Goussaud, Limousin, France
The term benchmark, bench mark, or survey benchmark originates from the chiseled horizontal marks that surveyors made in stone structures, into which an angle iron could be placed to form a "bench" for a leveling rod, thus ensuring that a leveling rod could be accurately repositioned in the same place in the future. These marks were usually indicated with a chiseled arrow below the horizontal line. A benchmark is a type of survey marker.
An Ordnance Survey cut mark in the UK
Occasionally a non-vertical face, and a slightly different mark, was used
An Ordnance Survey flush bracket
United States Coast and Geodetic Survey benchmark disk in the United States