There will have been moments of quiet reflection for the King on Monday.
Charles, Queen Consort Camilla, and the rest of the royal family marked a poignant personal anniversary ahead of the coronation on 6 May.
It was on 17 April in 2021 that the funeral service was held for Prince Philip, husband of the late Queen and the new King's father.
Philip died of 'old age' on the morning of 9 April 2021 at Windsor Castle at the age of 99. He was the world's longest-serving royal consort, having been married to the Queen for 73 years.
His wife was by his side at the time of his passing and she later said his death had left a "huge void" in her life.
At the time of Philip's funeral, coronavirus restrictions were still in place. It meant that only 30 guests were able to attend the service, including his grieving family.
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It also meant that the Queen had to sit alone; she was captured in a heartbreaking image quietly grieving by herself in the pews of St George's Chapel, prompting an outpouring of sorrow and sympathy from the public.
The then-Prince of Wales, Princess Anne, Prince Andrew and Prince Edward walked behind their father's coffin during the funeral procession, followed by Prince William and Prince Harry.
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The Queen marked the first anniversary of her husband's death with an emotional tribute. Watch below...
The Royal Family's official Twitter account released a video, comprised of a photo montage of the Prince over his long life. Included were photos of him as a baby, as a naval officer, with his four children, grandchildren, and great-grandchildren.
Perhaps most touching was an old photo of Philip leaning over his wife’s shoulder with their faces close together.
It ended with a recent black and white photo of the Duke tipping his hat as if to say goodbye.