Trig Points

A triangulation station, also known as a trigonometrical point or simply a trig point, is a fixed surveying station used in geodetic surveying. Although the familiar pillars are no longer used for their original surveying purpose, Ordnance Survey still owns many of them across the UK.

Alongside the pillars, Ordnance Survey installed a large number of smaller survey marks. I've recorded some of these on the Blocks & Intersected Stations page.