It is usually a hand-cast concrete pillar, 4 feet high and 2 feet square at the base, tapering towards a flat top. It is part of a network of surveying stations that were used by Ordance Survey for mapping. Each pillar is in view of several others so that their position may be triangulated.
Written on: 22/06/20:
Filed under:
open-data
Maps
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Written on: 21/02/17:
Filed under:
open-data