This trig (which isn't actually a trig but a benchmark) is also a YOSM so this is a 3 for 1 if you are a trig bagger and a cacher. 4 for 1 if you are also a benchmark bagger.
Please be careful as you need to park to the north and walk 120m along a VERY busy road. Not suitable for kids or dogs.
We planned on publishing this one in July but have brought it forward as we know there is a local event on and people might want to do this cache on the way.
Trigpoints are the common name for "triangulation pillars". These are concrete pillars, about 4' tall, which were used by the Ordnance Survey in order to determine the exact shape of the country. They are generally located on the highest bit of ground in the area, so that there is a direct line of sight from one to the next. By sitting a theodolite (an accurate protractor built into a telescope) on the top of the pillar, accurate angles between pairs of nearby trigpoints could be measured. This process is called "triangulation". A major project to map out the shape of Great Britain began in 1936. The network of triangulation pillars, with accurately known positions, led to the excellent OS maps which we enjoy today.