Princess Anne, 74, seemed to defy age as she stepped out wearing the Festoon tiara and styled her hair in a different style to usual – a twisted bun updo with a side parting, where she usually wears it in a bouffant style with stacks of volume at the root.
The switched-up look was strikingly similar to the hairstyle she rocked in her 23rd birthday portrait, where she also wore the Festoon tiara. In the black and white photos captured by Patrick Lichfield in 1973, Anne looked straight at the camera as she donned the diamond diadem from her own personal collection.
The tiara was presented to Anne in May 1973, just three months before her 23rd birthday, when she launched the 'World Unicorn' tanker on behalf of the World Wide Shipping Group.
While Anne has worn a number of tiaras since she wore her first in a formal photograph when she was 17 years old, the Diamond Festoon remains one of her favourites.
She wore it in 2017 to the Lord Mayor's Banquet at the Guildhall during a State visit by the King and Queen of Spain, and before that, at a State Banquet for President Sarkozy of France's State Visit at Windsor Castle.
For her most recent outing, Anne styled her tiara with a white gown with a lace trim and detailing on the bodice. Over the top, she put on a cropped jacket with short sleeves and wore a pair of three-quarter-length white gloves.
Tying her look together was a satin finish pink lipstick and a diamond necklace.
The day before her appearance at the State Banquet, Anne headed out on her own to the opening of the first tearoom of the Commonwealth War Graves Commission (CWGC) in Ypres, Belgium.
The royal wore a blue-green coat dress with slip-on block heels and her summer staple - a pair of wraparound sunglasses. Her sporty shades were previously a go-to accessory during her numerous appearances at the 2024 Paris Olympics.
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