After the war ended, Churchill ordered all of Bletchley's work — the computers, the notebooks — destroyed, but some of Alan Turing's notes were discovered between the walls of Hut 6 during a recent renovation, and are now on display at Bletchley Park.
Amongst the fragmented codebreaking documents located in the roof of Hut 6 were also parts of an Atlas, a pinboard and a fashion article form a magazine.
These are displayed alongside other items that were discovered during the restoration project and these include a fragment of 1940s' teapot, glass bottles including one for Chicory, archaeological items such as bricks from Block F (demolished in 1987) and a 'time capsule' left inside a door in Hut 11A.
The documents also included the only known examples of Banbury sheets, a technique devised by the mathematician Alan Turing to accelerate the process of decrypting Nazi messages. No other examples have ever been found.
BLETCHLEY PARK: Alan Turing's notes found being used as roof insulation in Hut 6 at Bletchley Park [Jessica Duncan/Mkweb]