Industrial History Online
Bletchley Park
Key Words :- Codebreaking Turing Bomb Enigma Colossus Lorenz GC&CS
Viewing the Site :- Now the Bletchley Park Museum - entrance fee payable
Address :- Tiltman Lane, Bletchley, Milton Keynes, Buckinghamshire, MK3 6DS
Grid Ref :- SP 86410 33869
Co-ordinates :- Lat 51.996553 , Long -0.742826
Local Authority :- Buckinghamshire Council
Pre 1974 County :- Buckinghamshire
Site Status :- Listed - Grade II
Historic England List No :- 1125409,
Site Condition :- Site conserved and open to the public
Site Dates :- 1938 -
Description and History of Site :-
Bletchley Park is a country estate that was bought by HMG just before World War II for military purposes. During the war, it accommodated the Government Code and Cypher (GC&CS), which successfully broke and transcribed the secret codes of the Germans, Italians, Japanese, Russians etc. In particular, it famously cracked Enigma - the day-to-day code between fighting units - and Lorenz, the code used by Hitler and his high command.
Some of the site was subsequently developed for housing, leaving two separated campuses. The first (this site) houses the Bletchley Park Museum; it is around the main mansion and includes it and the most historic huts and blocks.
The second is Block H (see separate site, ????) which housed the historic Colossus computer and is now home to the National Computer Museum. Colossus is of particular interest to industrial historians, being the world's first programmable digital electronic computer. It was designed partially on site and partially at the Post Office Research Station at Dollis Hill (qv), where it was also constructed.
Many of the streets in the adjacent development are named after key codebreakers and associated ephemera: Tiltman Lane, Colossus Way, Ultra Avenue, Welchman Court.
The main house was built in 1877 and was purchased by the Government for military use in 1938. As the war progressed, the site grew, with the addition of wooden huts in the grounds and brick and rc blocks that were nominally 'bomb proof', housing strategic operations. At its height, 9,000 people worked on the site.
Many codes were cracked and subsequently transposed, evaluated and disseminated by the various teams, including Alan Turing.
As well as the early developments in computing, the team in the Park also led improvements in data storage, data manipulation and dissemination processes. Bombes were designed on site; they were electromechanical devices that discovered some of the daily settings of the Enigma machines in the various German military arms. They were initially constructed in Hut 11.
Further Reading and References :-
Roberts J, 'Lorenz: Breaking Hitler’s Top Secret Code at Bletchley Park'. The History Press, 2017
Turing D, 'X, Y & Z: The Real Story of How Enigma Was Broken'. The History Press, 2018
Film: 'The Imitation Game', 2014: A Hollywood thriller, so don’t expect too much historical accuracy
https://en.wikipedia.org/wiki/Bletchley_Park
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Grid Ref :- SP 86410 33869
Co-ordinates :- Lat 51.996553 , Long -0.742826
Local Authority :- Buckinghamshire Council
Pre 1974 County :- Buckinghamshire
Site Status :- Listed - Grade II
Historic England List No :- 1125409,
Site Condition :- Site conserved and open to the public
Site Dates :- 1938 -
Bletchley Park is a country estate that was bought by HMG just before World War II for military purposes. During the war, it accommodated the Government Code and Cypher (GC&CS), which successfully broke and transcribed the secret codes of the Germans, Italians, Japanese, Russians etc. In particular, it famously cracked Enigma - the day-to-day code between fighting units - and Lorenz, the code used by Hitler and his high command.
Some of the site was subsequently developed for housing, leaving two separated campuses. The first (this site) houses the Bletchley Park Museum; it is around the main mansion and includes it and the most historic huts and blocks.
The second is Block H (see separate site, ????) which housed the historic Colossus computer and is now home to the National Computer Museum. Colossus is of particular interest to industrial historians, being the world's first programmable digital electronic computer. It was designed partially on site and partially at the Post Office Research Station at Dollis Hill (qv), where it was also constructed.
Many of the streets in the adjacent development are named after key codebreakers and associated ephemera: Tiltman Lane, Colossus Way, Ultra Avenue, Welchman Court.
The main house was built in 1877 and was purchased by the Government for military use in 1938. As the war progressed, the site grew, with the addition of wooden huts in the grounds and brick and rc blocks that were nominally 'bomb proof', housing strategic operations. At its height, 9,000 people worked on the site.
Many codes were cracked and subsequently transposed, evaluated and disseminated by the various teams, including Alan Turing.
As well as the early developments in computing, the team in the Park also led improvements in data storage, data manipulation and dissemination processes. Bombes were designed on site; they were electromechanical devices that discovered some of the daily settings of the Enigma machines in the various German military arms. They were initially constructed in Hut 11.
Roberts J, 'Lorenz: Breaking Hitler’s Top Secret Code at Bletchley Park'. The History Press, 2017
Turing D, 'X, Y & Z: The Real Story of How Enigma Was Broken'. The History Press, 2018
Film: 'The Imitation Game', 2014: A Hollywood thriller, so don’t expect too much historical accuracy
https://en.wikipedia.org/wiki/Bletchley_Park
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Contributor :- Tim Sidaway - 5 November 2026
Copyright :- cc-by-nc-sa 4.0 © Tim Sidaway
Copyright :- cc-by-nc-sa 4.0 © Tim Sidaway