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survey_point back to Key:man_made

Description: Triangulation pillars, geodetic vertices, and fixed equipment used by topographers (e.g. DGPS radio stations). Google definition User discussion

Element: help

Useful combination: name ref

Implies:

Used combinations in: Europe France Germany Italy Netherlands Spain Turkey Great-Britain Switzerland

Summary

These points are normally in a fixed location and of a known altitude used for the old fashioned trigonometry and cartography.

• See also http://en.wikipedia.org/wiki/Triangulation_station

How to Map

Add a node at the location of the trig point.centre of the watermill and use the man_made=survey_point. You can also add a name using name=*, its bracket number with ref=*, and its elevation using ele=*.

In the UK tpuk_ref=* can be used for its ID on the trigpointinguk.com website.