Bletchley Park was a Ministry of Defence monitoring base during World War II. Toshiko Sato's grandfather worked there. (TV: Greeks Bearing Gifts)
Bletchley Park was located in Buckinghamshire. The work of the Government Code and Cypher School, which involved teams of code-breakers cracking the Enigma and Lorenz cyphers, at Bletchley Park was vital to the war effort. Some historians estimate that the work done at Bletchley Park shortened the war by as much as four years. (PROSE: A History of Humankind)
Alan Turing was chief cryptologist at Bletchley Park until he left to work at Hanslope Park. Hugh Alexander replaced him, but called Turing back in December 1944 after discovering a new code being transmitted from Dresden. With the help of the Eighth Doctor, they discovered that the code was alien in origin. (PROSE: The Turing Test) Turing's team was known as the Cambridge Group; its most notable member was Rachel Jensen. (PROSE: Remembrance of the Daleks, Who Killed Kennedy) The future Reverend Foxwell also worked with Turing. Professor Stream also claimed to have worked there, but this turned out to be false. (AUDIO: The Hollows of Time)
Before her marriage to Edward Grainger, Eleanor Grainger worked at Bletchley, at first as a "glorified typist", then she received a minor promotion. She met George Tremayne there, who courted her for six months. (PROSE: Ancient Whispers)
In 1943, Commander A. H. Millington believed that the Seventh Doctor and Ace were from Bletchley, sent by the Army to discover the details of ULTIMA, but Dr. Judson assured him that they'd never heard of him there. (PROSE: The Curse of Fenric)
In 1944, the Sixth Doctor worked there for several months. While there, he met his companion Constance Clarke. He believed that Bletchley almost put Logopolis to shame. (AUDIO: Criss-Cross)
Bletchley Park's least successful hut was run by Professor Sidney Ornadel. (AUDIO: Ashenden)