Her Majesty was gifted the impressive life-size playhouse when she was six years old. The giant Wendy House sits in the gardens at the Royal Lodge in Windsor, where the Queen lived as a child.
The playhouse has been kitted out with running water, electricity, a fully-functioning kitchen and bathroom and even a living room and bedroom.
The Queen and her sister Princess Margaret are said to have spent much of their childhood playing in the impressive Wendy House.
Having grown up in the Royal Lodge herself, Princess Beatrice also played in the cottage.
In 2012, Beatrice told Andrew Marr she helped Her Majesty renovate the miniature property.
Speaking on the documentary The Diamond Queen, she said: “Granny and her sister played here growing up and we’ve been lucky enough to play here with cousins and second cousins and it’s a big family treat.”
Princess Beatrice admitted it is the “most glamorous Wendy House ever”.
She revealed how the Queen had a “very clear” message on how she wanted her playhouse to be re-designed.
Princess Beatrice described how the house has now been “completely rethatched” and has “new curtains and new wiring”.
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“I’ve been lucky enough to play here and now Granny’s a great-granny, so now the great-grandchildren can enjoy it too.”
The Queen has eight great-grandchildren.
The Duke and Duchess of Cambridge have three children – Prince George, seven, Princess Charlotte, five, and Prince Louis, two.
Princess Anne’s son Peter Phillips and wife Autumn’s two children, Savannah and Isla, are also great-grandchildren to Her Majesty.
Princess Anne’s only daughter Zara Tindall and husband Mike also have two daughters Mia and Lena – and are expecting another child this year.
Lastly is Prince Harry and Meghan Markle’s baby son Archie, who is the Queen’s eight great-grandchild.
All of Her Majesty’s young relatives could have the chance to play in her huge Wendy House.
The two-thirds scale thatched playhouse was a gift to the Queen, the then Princess Elizabeth, from the people of Wales.
Normally the Royal Family are unable to accept public gifts.
However, as the present was given to Her Majesty herself and not the Royal Collection Trust, she was able to keep it.