Tag:man_made=survey_point

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Public-images-osm logo.svg man_made = survey_point
Trig Point near Wootton Wawen.jpg
Description
A triangulation pillar, geodetic vertex, or other piece of fixed equipment used by topographers. Edit or translate this description.
Group: Man made
Used on these elements
may be used on nodesshould not be used on waysshould not be used on areasshould not be used on relations
Useful combination
Wikidata
Status: de facto

A survey point is a triangulation pillar, geodetic vertex, or other piece of fixed equipment used by topographers. An example of these are DGPS radio stations. These points are normally in a fixed location and of a known altitude used for the old fashioned surveying.

See also Triangulation station and Benchmark (surveying).

How to map

Add a node at the location of the trig point and use the man_made=survey_point.

Additional tags

  • name=*
  • ref=* its bracket number. See the discussion page for comments on 'bracket number'.
  • ele=* its elevation using (use the height reference system specified in ele=*!)
  • survey_point=*: this key seems like a mess, please comment on how to interpret or split this key (can contain dozens of values, like bm_new, trig_3rd, suppl, forest_trig, mine, bm_cgs, taipei, suppl_TW, polygon_IT, sectionstake, satellite_1st, trig_2nd, ...)

Possible Rendering

Man made survey point.svg suggested by User:Chrisana13

example bracket on a UK trig point, tag with ref=S8325

Additional tags

  • aerial=yes for extra markings meant to be visible in aerial photographs - a white cross, usually
  • In the UK tpuk_ref=* can be used for the ID of a trig point on the trigpointinguk.com website.
  • Since multiple survey points are possible on one object (eg. a benchmark on a triangulation point/pillar) then in order to avoid multiple values within one key, such as a semicolon-delimited list in survey_point=*, it may be advisable to use something like triangulation_point=yes and benchmark=yes to allow clean coexistence of tags on one node.