The King and Queen exchanged comforting looks as they were crowned at their joint coronation service at Westminster Abbey.
Camilla, 75, wearing an embroidered Bruce Oldfield dress, was seen looking over at her husband proudly after she was crowned with Queen Mary's Crown by the Archbishop of Canterbury.
Her decision to use Queen Mary's Crown is the first time a consort's crown has been recycled for a coronation rather than a new one created.
It has been altered, with four of the eight detachable arches removed to create a different impression.
It used to feature the controversial Koh-i-Noor diamond, but the gem was not used and the crown was adapted to include the Cullinan III, IV and V diamonds – from the late Queen’s personal jewellery collection.
Take a look at the sweet moment between the King and Queen in the video below…
It followed the moment the King was presented with St Edward's Crown, which was placed on his head by the Archbishop.
It will be the only time in his life that Charles will wear the 360-year-old crown, which is made of solid 22-carat gold, is over 30cm (1ft) tall and weighs around 2.23kg (nearly 5lbs).
The congregation then proclaimed, "God Save the King!" as the Abbey bells rang, trumpets sounded, and gun salutes were fired across the UK.
At the conclusion of the two-hour service, the King and Queen changed into their purple Robes of Estate, with the King putting on the Imperial State Crown.
SEE: Watch Prince Harry confirm his speedy UK exit during coronation ceremony
The couple then travelled back to Buckingham Palace in the 261-year-old Gold State Coach, with members of the royal family in the carriage procession behind them, including the Prince and Princess of Wales and their three children, Prince George, Princess Charlotte and Prince Louis.
The next carriage contained the King's youngest brother the Duke of Edinburgh with his wife the Duchess of Edinburgh and their children Lady Louise Windsor and the Earl of Wessex.
The late Queen's cousin the Duke of Gloucester and his wife the Duchess of Gloucester, and Anne’s husband Vice Admiral Sir Tim Laurence travelled in the third carriage,
Following by car were the Duke of Kent and Princess Alexandra, also cousins of Elizabeth II, and completing the procession of royals.
The Duke of Sussex and Camilla's immediate family from her first marriage to Andrew Parker Bowles were also among the congregation, but did not form part of the procession.
Thousands of royal fans braved the rain to line the route through central London.
More than 4,000 ceremonial troops took part in the procession, escorting the King and Queen back to the palace.
The couple will receive a royal salute from the military assembled in the palace gardens, before the day concludes with an appearance on the balcony to watch the flypast.
The King and Queen celebrated their 18th wedding anniversary last month. The pair tied the knot in a civil ceremony in Windsor in 2005.
Charles became monarch following the death of his mother, Queen Elizabeth II, in September 2022.
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