These usually takes the form of a horizontal line with an arrow pointing up from below.
These marks were cut by Ordnance Survey levelling staff to provide a network of points at which height has been precisely measured (to the centre of the horizontal line) above sea level.
It was policy to maintain about 5 bench marks per 1Km square in rural areas, about 30 to 40 in urban areas, and there was a policy to check and renew marks to compensate for losses due to building and road works.
There used to be about half a million bench marks in Great Britain but they are not needed any more and about half have disappeared.
You can find them mainly on buildings (especially churches) and on bridges.
The name derives from the angle iron which is fitted into the horizontal cut to give a ‘bench’ or support for a levelling staff. I can only believe that the stoop was there long before the Ordnance Survey decided to use it.
Difficult to know the exact age of its erection.
|Heading towards Bleakholt|
|A close up of the bench mark|
|Looking back up the path towards the Wind Farm|
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