Happy birthday to the trig pillar, 80 years old today 18 April 2016 gsvalentineblog 1 Comment Ordnance Survey (OS) is celebrating the 80th anniversary of the triangulation pillar. Share this: Share on Bluesky (Opens in new window) Bluesky Share on Facebook (Opens in new window) Facebook Share on WhatsApp (Opens in new window) WhatsApp Share on X (Opens in new window) X Like this:Like Loading...
