Triangulation station

Common card · No. 442501

A triangulation station, also known as a trigonometrical point, and sometimes informally as a trig, is a fixed surveying station, used in geodetic surveying and other surveying projects in its vicinity. The station is usually set up by a mapping organisation with known coordinates and elevation published. Numerous stations are installed on summits for purposes of visibility and prominence. A graven metal plate on the top of a pillar may provide a mounting point for a theodolite or reflector, often using some form of kinematic coupling to ensure reproducible positioning.

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