Survey marker

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In surveying and geodesy, a marker (also called a mark, monument, or station) is an object firmly installed to indicate points on the Earth's surface with known coordinates. A benchmark is a type of survey marker that indicates elevation (vertical position). Horizontal position markers used for triangulation are also known as triangulation stations. A set of interrelated geodetic markers form a geodetic network. An active station or reference station is occupied permanently with a measurement instrument, such as GPS/GNSS continuously operating reference stations (CORS). Benchmarking or trigpointing is the hobby of searching for these marks.

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