English: Hut 3 at Bletchley Park with a rebuilt blast wall. The decrypted messages that had been enciphered with the Enigma machine, the Lorenz cipher machine (codenamed Tunny) and other sources, were translated and synthesised into "Ultra" Military intelligence here during WWII. The function later moved into Block D but kept the name "Hut 3", the building being renamed Hut 23.