Regular readers of my blog will know I have a fascination with trig points, the concrete pillars that were used to map Britain (or at least one of the methods used).
Today is the 75th anniversary of first observations made using a triangulation pillar and the beginning of the Retriangulation of Great Britain. The pillar in question is located in Cold Ashby, Northamptonshire and unfortunately I was unable to join the small group of devotees who made a pilgrimage to the pillar today.
The Ordnance Survey have marked the anniversary with a special blog Happy birthday to the Trig Pillar – 75 years young today” href=”http://blog.ordnancesurvey.co.uk/2011/04/happy-birthday-to-the-trig-pillar-75-years-young-today/” target=”_blank”>post today and I understand that the pillar in question will be featured on the local BBC news bulletin.
I have long been aware of trig points, although it wasn’t until recent years that I really began to appreciate their history and function. For a long time I knew they were used in map making and were a physical reminder that I had reached the top of a hill, but now I know a lot more about their history and their part in producing the maps that I still use today.
So happy anniversary to the trig point, and because I can’t be at Cold Ashby here is one of my favourite trig points instead, at Blackcap near Lewes, East Sussex.