It’s a staple in Hollywood films featuring grand mansions, castles or palaces that there’s always a secret door or two somewhere. Apparently, even Queen Elizabeth II has one, and it’s cleverly concealed in plain sight.

Actually, it’s not just a secret door. There’s a secret passage attached to it as well, so Her Majesty can travel from her private living quarters to the Palace’s center without anyone noticing her.

Buckingham Palace’s secret passage connects Queen Elizabeth’s living areas directly to the White Drawing Room. The room is said to be the grandest among Buckingham’s many State Rooms and serves as the reception room where Her Majesty and members of the royal family gather right before official functions.

However, the secret passage’s door located in the White Drawing Room is so cleverly designed that guests would not notice that it’s actually a door. There’s a normal-looking cabinet located in a corner that can be pulled open to one side, revealing another door behind it.

If the cabinet is not ajar, guests would assume it’s just another furniture, one of the many pieces inside the White Drawing Room. Compared to the other cabinets, the only difference of this one is that all the ornaments contained inside are glued so they won’t fall off when the cabinet is moved to reveal the doorway.

Queen Elizabeth’s secret door at Buckingham Palace is not a rarity among palaces. Tunnels, secret rooms and passageways can be considered a norm among ancient castles and palaces as they were considered a necessity for royalty, aristocrats and other wealthy members of society.

In those turbulent times of the past, these tunnels and passages can be used as a stealthy escape route for members of royalty and aristocrats. They can be used by royals to easily evade the pursuit of their enemies and can be viewed as a form of life-saving measure incorporated into the design of the castle or palace.

Secret rooms and passages can also be used as venues for secretive meetings. Since palace occupants’ movements can’t be tracked, alliances can easily be kept a secret. Secrets doors and passages are a handy feature to have for those who are engaged in political maneuvering.

Queen Elizabeth II Queen Elizabeth II poses for a photo after she recorded her annual Christmas Day message in the White Drawing Room at Buckingham Palace in a picture released on December 25, 2018, in London, United Kingdom. John Stillwell - WPA Pool/Getty Images