Design of new Alan Turing £50 note revealed – GCHQ launches ‘most difficult puzzle ever’ to honour the code breaker

A new Bank of England has revealed the design of the new £50 note featuring code-breaker and national hero Alan Turing.

The new polymer £50 note contains advanced security features, completing our most secure set of Bank of England polymer banknotes yet.

The note, like the £20, incorporates two windows and a two-colour foil, making it very difficult to counterfeit.

There is also a hologram image which changes between the words ‘Fifty’ and ‘Pounds’ when tilting the note from side to side.

The banknote will enter circulation on 23 June, which would have been the mathematician’s birthday.

GCHQ, the UK’s intelligence, security and cyber agency has launched its most difficult puzzle ever – the Turing Challenge – in honour of Alan Turing becoming the new face of the £50 note.

Turing is the father of modern computing, a pioneer in artificial intelligence, and instrumental in breaking the German Naval Enigma cipher at Bletchley Park – GCHQ’s wartime home – during the Second World War.

Director GCHQ Jeremy Fleming said

“Alan Turing’s appearance on the £50 note is a landmark moment in our history.”

“Not only is it a celebration of his scientific genius which helped to shorten the war and influence the technology we still use today, it also confirms his status as one of the most iconic LGBT+ figures in the world.”

“Turing was embraced for his brilliance and shunned for being gay.”

“His legacy is a reminder of the value of embracing all aspects of diversity, but also the work we still need to do to become truly inclusive.”

The Turing Challenge, a set of 12 puzzles, has been put together by some of GCHQ’s intelligence staff, where problem solving and a diverse mix of minds are at the heart of thier work to help protect the UK from increasingly complex threats.

The puzzles are based on the unique design elements of the new banknote, such as the technical drawings for the British Bombe, the machine designed by Turing to break Enigma-enciphered messages during WWII. GCHQ puzzlers say the full challenge could take an experienced puzzler seven hours to complete.

Colin, a GCHQ analyst and chief puzzler, explains

“Alan Turing has inspired many recruits over the years to join GCHQ, eager to use their own problem-solving skills to help to keep the country safe.”

“So it seemed only fitting to gather a mix of minds from across our missions to devise a seriously tough puzzle to honour his commemoration on the new fifty pound note.”

“It might even have left him scratching his head – although we very much doubt it!”