Queen pays tribute to Bletchley Park Enigma codebreakers
The Queen is to pay tribute to the codebreakers who worked at Bletchley Park, the secret cypher base in WWII which broke the German Enigma codes.
She will visit the site in Milton Keynes with Prince Philip, and unveil a memorial to the men and women who worked there.
Some historians believe that breakthroughs made there shortened the war by two years.
Nicholas Witchell reports.
15 Jul 2011