updated 06/18/2014 AT 11:00 AM ET
•originally published 06/18/2014 AT 12:20 PM ET
The Duchess of Cambridge got an insight into her family history when she met a woman who worked alongside her grandmother at a World War II code-breaking center.
On Wednesday, Kate, 32, was at Bletchley Park, the secret wartime spy base brought to life in the movie Enigma starring Kate Winslet. The base’s historic huts where the code breakers worked have been renovated to look like they did 70 years ago.
And Kate looked the part. She dressed in a 1940s-style navy pencil skirt and cream outfit by Alexander McQueen and sapphire and diamond earrings that once belonged to her late mother-in-law, Princess Diana.
Kate’s paternal grandmother, Valerie Glassborow, and her twin sister, Mary, worked in Hut 6 as duty officers in the “Cover Management Y” team that identified interception sites and signals that were suitable for monitoring. They would then pass the information on to code breakers.
The pair had come from administrative jobs at the Foreign Office.
When Kate met the twins’ friend Lady Marion Body, 90, she wanted to find out all she could about the role Valerie – who later married Kate’s grandfather Peter – played.
“When I was a young girl, I did ask Granny about it,” she told Lady Body.
But like many of the era, she didn’t pass along all their stories of wartime work.
“Valerie died a few years ago and it was only fairly recently that people felt able to talk about it,” Lady Body tells PEOPLE. “She’d go and tell her father.”
A key moment was when Lady Body told Kate of how they learned that the Japanese wanted to surrender. “We sat there in complete silence for about a minute before we were told to get on with our work. The duchess didn’t know that story.”
And she says of Kate, “She’s lovely, she’s absolutely wonderful.”