GCHQ Puzzles Sep 22
This is aimed at a younger audience and the general reader. Founded after the Great War, the original GCCS was a secret establishment for the interception and decryption of signals. It set up shop at Bletchley Park during World War II and is now the UK Government Communications Head Quarters.
Examples of puzzles will follow when they become public. Meanwhile, here is a short zine of Square Ciphers to keep you going.