Along with other members of the royal family, Her Majesty shunned a traditional black garment and opted to wear green as a subtle tribute to the late Duke of Edinburgh, whose livery colour was Edinburgh Green.
WATCH: The Queen arrives at Prince Philip's Service of Thanksgiving
However, when she arrived alongside her son Prince Andrew, the monarch made a quick wardrobe change before she walked inside. She was seen wearing some stylish sunglasses before taking them off and adding a coordinating green hat.
The symbolic choice of green was a fitting way to remember the Queen's late husband as the colour was used over the years for things like his staff liveries and private cars, including the driving carriage at his funeral last April.
The shade could also celebrate Philip's long-standing association with the Rifles Regiment, who wear a green uniform. The late royal had been Colonel-in-Chief of the Regiment from 2007 until 2020, when he handed over the role to daughter-in-law Duchess Camilla.
The Queen seen with her sunglasses as she arrived with Prince Andrew credit Peter Macdiarmid/LNP
For the occasion, the Queen was joined by close family, friends, foreign royals and hundreds of charity workers in remembrance of her beloved husband the Duke of Edinburgh at the poignant memorial service. Prince Andrew escorted his mother into Westminster Abbey.
The monarch held onto his elbow with her left hand as she moved slowly and gingerly to her place, using a walking stick in her right hand. They entered via Poets Corner - a shorter route for the Queen's comfort - in a small procession.
The Queen later ditched the sunglasses for her hat
Among those attending were Prince Charles, the Duchess of Cornwall, the Duke and Duchess of Cambridge, Prince Edward, the Princess Royal, Princess Beatrice, Princess Eugenie as well as their respective husbands Edoardo Mapelli Mozzi and Jack Brooksbank.
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