Over the weekend I have learned that the Post Office Tower was a national secret, and didn’t appear on any OS maps from it’s completion in 1966 till it was finally declassified under parliamentary privilege in 1993.

Despite being the tallest building in London and open to the public as a restaurant for most of that time.

I find this to be completely brilliant, and part of me wonders why no one told me.*

* I asked my brother about this, to be told “That he couldn’t tell me as it was a secret”!