It is a small slip of paper, not much bigger than a credit card, but its import to the men and women of Bletchley Park would have been paramount. They would have been among the first to hear of Hitler's suicide and at that point perhaps were able to look back upon their many months or years of hard work that helped bring the war closer to its conclusion.

The home of British codebreaking during World War Two, Bletchley Park near Milton Keynes played a major role in producing secret intelligence which had a direct and profound influence on the outcome of the conflict.

Sinclair McKay's carefully researched book, Secret Archives gives insight into the highest level of security work going on in the Buckinghamshire countryside - the code breaking and cipher cracking as well as the plots and to cease German dominion over Europe and those of her allies in Japan, North Africa and Italy.

We hear of their lives beyond service at Bletchley where civilian life was particularly unchallenging especially for the female operatives among them xxxx

The author also has an enthusiasm for James Bond so to add to our enjoyment he has ingeniously secreted bits of information in a series of special pockets as though we have been sent on a top secret mission with maps and documentation that we must keep safe from enemy eyes. Ian Fleming's contribution to a stealth raid involving a stolen Luftwaffe plane is among them as are notations by Alan Turing, the D Day landings and the brief message detailing the death of the Furher.

Bletchley Park is open to the public and has interactive exhibits so visitors can experience first hand the types of problem solving activities used to decrypt the German Enigma messages, plus extra half term activities include free Codebreaker trails and collage workshops inspired by Morse Code.

www.bletchleypark.org.uk