The Queen's jewels were hidden in a cookie tin during the war

By Ainhoa Barcelona

During the Second World War, the royal family's Crown Jewels were hidden in a very clever and unexpected spot: a cookie tin! The revelation comes courtesy of a new documentary. King George VI ordered that the precious stones be buried under a secret exit from the Windsor Castle called sally port, which was used in times of emergency. The collection included the Black Prince's Ruby from the Imperial State Crown, taken from London to Berkshire for fear they could one day fall into the hands of the Nazis.

A new BBC documentary, The Coronation, reveals the true story. The Queen, who stars in the programme due to air on Sunday, was aware of the general story, but did not know the details until told by royal commentator Alastair Bruce. Mr Bruce, who presents the documentary, told The Times: "What was so lovely was that the Queen had no knowledge of it. Telling her seemed strangely odd."

TAP TO VIEW THE GALLERYQueen Elizabeth II and Alastair Bruce posing in their chair at BBCThe Queen with royal commentator Alastair Bruce

The story about the Crown Jewels was discovered after a set of letters from Sir Owen Morshead, the royal librarian to Queen Mary, the mother of George VI, shed light on the mystery. Sir Owen's documents describe how a hole was dug in chalk earth, which had to be covered to hide it from enemy bombers, and two chambers with steel doors created. A trap door used to access the secret area where the tin box was kept still exists today.

In the documentary, the Queen gives a rare insight into her life as head of state. She speaks about the perils of wearing the 1.28kg Imperial State Crown, and revealed that you can't look down when wearing it. "You can't look down to read the speech, you have to take the speech up," she says. "Because if you did your neck would break, it would fall off. So, there are some disadvantages to crowns, but otherwise they're quite important things.'"

Throwback: a young Queen Elizabeth II wearing her crown and scepter at her CoronationA new BBC documentary, The Coronation, centres around the Queen's milestone

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The documentary centres around the Queen's coronation in 1953, and takes a look in detail at the Imperial State Crown, which was made for George VI's coronation in 1937. Her Majesty observed: "Fortunately, my father and I have about the same sort of shaped head. But once you put it on, it stays. I mean, it just remains on." The crown is set with 2,868 diamonds including 17 sapphires, 11 emeralds and hundreds of pearls, including four known as Queen Elizabeth I's earrings. It also features the Black Prince's Ruby.

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