Non-OS marks

A Facebook page is available for discussing the larger-sized non-OS stations. Environment Agency Control Stations (EACS) or Benchmarks (EABM) have been created since the 1990s for use as survey control for Environment Agency projects. Control stations are fixed locations which have been accurately surveyed using GPS / GNSS data and are often near Environment Agency structures. There is a site for logging EABM markers. A non-OS pillar such as Rob’s Pillar may sometimes be encountered. This was installed for Rob Newgent’s 40th birthday by his friends. It has a flush bracket, with ‘Rob’ on the side and was added to TrigpointingUK soon after. Numerous other bolts, rivets and miscellaneous markers exist. These are often found in pavements, bridges and along river banks. Their purpose is sometimes obscure and uninteresting. Here are a few examples:

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  rivet on a step approx locn SE 2807 3702
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  National Rivers Authority block
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  National Rivers Authority bolt
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  National Rivers Authority bolt
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  Environment Agency Bench Mark
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  Environment Agency Bench Mark
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  'Survey Point' (pavement)
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  'M A G' (pavement)
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  NRA Fenomark
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  Groundmark - gas pipeline?
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  GPO cable marker; not a benchmark
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  Military boundary marker; not a benchmark