Trig point

At the weekend I climbed up to the trig point on the top of Baildon Moor. It's an exhilarating climb, especially when it's as windy as it was on Sunday. It's not that high really (282m above sea level) but it still makes a good afternoon's walk. From the top you can see across the moors - my photo is looking towards Ilkley Moor - and look right across to the city of Leeds, as well as over to Bradford and down to Saltaire at the foot of the hill. You can also watch planes taking off and landing at Leeds-Bradford airport, a few miles away.

Trig points (triangulation stations) were a tool for surveying the UK, in the days before aerial photography and electronic positioning aids (GPS) were available. There are over 5000 of them across Britain. A trig point is usually a concrete post, set on a high point such as a hill, with a metal disc in the top into which you can slot a theodolite. The trig point is at an accurately surveyed and documented position and (on a clear day) has at least two other trig points in view, so the whole country is divided into triangles. They are mostly redundant now, except as a goal for hill-walkers to aim for. After the exertion of the climb there's quite a thrill in reaching the trig point! (And then eating your sandwiches or getting out your thermos flask for a well-earned cup of tea!)