Trig Point

When you are out and about in the countryside, chances are you’ll come across one of these concrete pillars which once played a crucial role in helping to make Britain’s maps.

They were used by the Ordnance Survey, Britain’s map making agency, and were known as trig points, or pillars, even benchmarks.
The Survey itself says between 1936 and 1962 around 6,500 of them were built, usually on high land, and were used as a solid base for theodolites which were then used by the mapmakers in surveying the countryside..
Today, they use satellite technology to map detail on the ground, but there are still a number of these pillars around the country, although now redundant, like this one on Canada Common in the New Forest.