Kate Middleton meets budding codebreakers at Bletchley Park – see best photos

The Duchess of Cambridge made a fascinating visit to Bletchley Park on Tuesday to meet young children taking on the role of codebreakers. Kate was viewing a special D-Day exhibition to mark the 75th anniversary of the D-Day landings, and joined a group of youngsters in their codebreaking workshop. The boys and girls re-enacted what it was like in June 1944 to intercept and decipher German communications.

Kate, who looked ultra-glam in a polka dot dress, was given a tour of the interactive exhibition, D-Day: Interception, Intelligence, Invasion. She also met with those who helped restore the Teleprinter Building. During the Second World War, codebreakers received hundreds of thousands of enemy messages in the building, intercepted at secret listening posts across the UK.

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Kate arrived at Milton Keynes in the early afternoon, having travelled from London. The Duchess waved to crowds who gave her a very warm welcome outside Bletchley Park.

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The mother-of-three embraced the sunshine in a navy blue polka dot dress by Alessandra Rich, which featured a daring split.

A closer look at Kate's chic outfit.

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The mother-of-three wore her hair loose and as always, she used natural makeup to give her a fresh glow.

The Duchess received a posy from one adorable youngster.

Prince William's wife last visited Bletchley Park in 2014. During the visit, she met with veteran codebreakers who worked at Bletchley alongside Kate's grandmother Valerie Glassborow, and her twin sister Mary, during the Second World War.

The royal bonded with a group of youngsters taking part in one of Bletchley Park Trust's learning activities – a codebreaking workshop. She spoke to schoolchildren from Akeley Wood Primary School who were learning to code using enigma machines.

"My granny and her sister worked here. It's very cool. When she was alive sadly she could never talk about it," Kate told them. "She was so sworn to secrecy that she never felt able to tell us."

The Duchess also spent time with four women, who had worked at Bletchley at the same time as her relatives: Rena Stewart, who worked in Hut 3; Georgina Rose, a Teleprinter Operator and Morse Code Slip Reader in Block E; Elizabeth Diacon, a Teleprinter Room Supervisor, serving Hut 3, Hut 6 and Hut 8; and Audrey Mather, a Teleprinter Operator who was based in Block E.

"You were very important," the Duchess told the women. "Your families must be very proud."

Kate was given a tour of the exhibition in the newly restored Teleprinter Building. The exhibition includes an immersive film, based on newly declassified material, which shows how the intelligence effort coordinated at Bletchley Park helped specifically in the success of the D-Day landings at Normandy. Using sophisticated codebreaking techniques, workers at Bletchley Park fed crucial information to Allied forces in the critical months, weeks and days leading up to D-Day on 6 June 1944.