The 94-year-old was seen driving a green Jaguar out of Windsor Castle wearing a bonnet and sunglasses as she drove out of the grounds.
A guard was seen nearby as she headed to Frogmore Gardens - near where grandson Prince Harry is isolating at Frogmore Cottage.
The Queen is "bearing up well" amid the final preparations for the funeral, according to The Sun.
Her Majesty is said to be "in control" despite the reported rift between Prince William and Harry as well as the row over the Duke of York wanting to wear a naval uniform to the funeral.
Due to coronavirus restrictions, only 30 people will be in attendance at the funeral with crowds being urged to stay away from Windsor as even Prime Minister Boris Johnson stepped aside to make way for an additional family member.
Mr Johnson left flowers outside St George's Chapel at Windsor Castle with a note that read, "In grateful memory of a man to whom the nation owes more than words can say.
"Sent on behalf of the nation. From the Prime Minister."
The Queen shares candid photo of herself and Philip
The Queen has shared a sweet candid photo of herself and Prince Philip taken during a trip to the Scottish Highlands in 2003.
The photo, which was taken by Prince Edward's wife Sophie, the Countess of Wessex, shows the couple at the top of the Coyles of Muick smiling and looking relaxed while sitting on the grass.
The pair seem completely at ease and smile warmly for the camera.
"Her Majesty and the Royal Family are grateful for all the messages of condolence from around the world and have been touched to see and hear so many people sharing fond memories of The Duke, in celebration of his life," the caption read.
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