Princess Eugenie's husband Jack Brooksbank has spoken out about the palace's secret underground tunnels, according to Daily Mail's royal editor, Richard Eden.
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The journalist reported that Jack opened up to him during a Casamigos event, which is the tequila brand that the father-of-one works for.
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"There is one from Dukes Bar to St James's Palace. I haven't used it yet, but I'd love to check it out," he reportedly said.
It's not the first time we've heard about the possibility of secret royal tunnels though. And in London, it seems quite feasible considering that there was a network of underground passages built below the city to be of use during wartime.
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Windsor Castle has a hidden tunnel
And it's not just St James's Palace with these concealed routes!
In a BBC documentary, The Queen's Palaces, Fiona Bruce revealed that Windsor Castle has a top secret passageway – and the hidden exit is like something out of a James Bond film.
As the newsreader showed viewers into a seemingly normal, unassuming room, she said: "This is an office just tucked away in a corner of Windsor Castle. But look under here."
Under the carpet, the presenter uncovered a wooden trapdoor leading to a secret tunnel. "As if by magic, just lift these and the medieval castle emerges," she said.
The Queen has a secret door too
It was also reported in Finding Freedom that Prince Harry and Meghan Markle would use Kensington Palace's secret entrance to pop up onto the high street when required. "No front entrance for the pair. They were given directions for how to get into the building using a discreet door away from prying eyes," it read.
Plus, we know the Queen is partial to a secret entrance or two as the White Drawing Room at Buckingham Palace has a hidden door behind a mirror which leads directly to the monarch's private state apartments.
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