Bletchley Park was once Britain's best kept secret, with all activity undertaken there strictly hidden for three decades after the war ended.
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The women of Bletchley Park —
Tall, barbed wire laden fences surrounded the park, with guards positioned at the gate ensuring maximum security at all times.
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The women of Bletchley Park —
At one of Bletchley's outposts in East Cote, some 72 women could be sharing a dormitory at any one time.
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The women of Bletchley Park —
A propaganda sign reading 'Don't waste here the fuel you save at home!' can be seen on the wall here at Bletchley Park.
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The women of Bletchley Park —
When Bletchley's recruits signed their work agreements, the contracts stipulated that they would be employed there until the war ended - whenever that might have been.
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The women of Bletchley Park —
Working was often a lonely experience, with the estate's inhabitants strictly forbidden from discussing their roles with fellow colleagues and roommates.
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The women of Bletchley Park —
People drafted in as codebreakers were often found by tests requiring them to complete The Daily Telegraph's crossword in under 12 minutes.
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The women of Bletchley Park —
All workers at the estate were ordered to sign the Official Secrets Act. For many young girls at the park, this meant that their families had no idea where their 18-year-old daughters had been sent.
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The women of Bletchley Park —
Margaret Bullen, pictured, began working on the Colossus machine in 1943. Bletchley's culture of secrecy meant she only discovered its name some decades later.
Courtesy Margaret Bullen
The women of Bletchley Park —
Margaret pictured today in front of the rebuilt Colossus machine at The National Museum of Computing.
Courtesy James Martin
The women of Bletchley Park —
Her Majesty the Queen visited Bletchley Park in 2011, and received an Enigma machine demonstration from Ruth Bourne (interviewed below). The monarch called the contraption "splendid."
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The women of Bletchley Park —
A number of Bletchley's former recruits now offer their services as guides for visitors at the Trust.
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