The royals were out in force today as they celebrated the King's first birthday parade, known as Trooping the Colour.
King Charles and Queen Camilla were joined by the the Prince and Princess of Wales, the Princess Royal, and the Duke and Duchess of Edinburgh at the spectacular event in central London.
It was a milestone moment for Charles as he marked his first official birthday parade of his reign, since his accession to the throne last September.
It was also the first time a monarch has ridden on horseback since the late Queen Elizabeth II rode on her beloved horse, Burmese, in 1986.
The King was joined in the parade by the Princess Royal, who is the Senior Colonel of the Household Division, as well as the Prince of Wales, and for the first time, the Duke of Edinburgh.
Queen Camilla, the Princess of Wales and the Duchess of Edinburgh watched proceedings from the carriages.
William and Kate's children Prince George, Princess Charlotte and Prince Louis, also joined Camilla and Kate in the carriage procession. See the royal children's arrival in the clip below...
Princess Kate arrives with Queen Camilla and children
In a royal first, Queen Camilla and the Princess of Wales attended the event for the first time with their military roles. Camilla is Colonel of the Grenadier Guards, while Kate is Colonel of the Irish Guards.
The Queen's symbolic red silk coat dress takes inspiration from the uniform of the Grenadier Guards. The dress incorporates key details from the uniform including the 'The Grenade Fired Proper' embroidered in gold bullion on the collar and the gold bullion back slashes. Camilla accessorised with a black beret-style cap with a feather plume, in a nod to the bearskins that the regiment wear.
Meanwhile, the Princess of Wales looked lovely in a green dress by Andrew GN, in a nod to her role as Colonel of the Irish Guards. She accessorised with a wide-brim hat by Philip Treacy.
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George and Louis matched in navy suits and red ties, while Charlotte wore a sweet red and white dress with wide lapels.
The Duchess of Edinburgh joins carriage procession
Leading the carriage procession were the Duchess of Edinburgh, who wore a cream dress with fluted sleeves, and the Princess Royal's husband, Vice Admiral Sir Timothy Laurence.
Also joining the royals in the carriage procession were the late Queen Elizabeth II's cousins, the Duke and Duchess of Gloucester.
King Charles rides on horseback
King Charles had a royal first at Trooping the Colour as he rode onto Horse Guards Parade in Whitehall as the nation's head of state.
He was joined on horseback by the royal colonels – the Prince of Wales, Colonel, Welsh Guards; the Princess Royal, Gold Stick in Waiting and Colonel of The Blues and Royals; and the Duke of Edinburgh, riding for the first time in his role as Colonel of the 1st Battalion London Guards, formed last year.
Anne was dressed in the full ceremonial uniform of the Blues and Royals, while William donned the uniform of the Welsh Guards and Edward wore the full ceremonial Guard Order of the London Guards.
The royals watch the flypast from the Buckingham Palace balcony
King Charles and Queen Camilla were joined by senior working members of the royal family to watch the incredible military flypast from the Buckingham Palace balcony following the parade.
The Prince and Princess of Wales were joined by their children, with Louis enthusiastically waving and saluting as the aircraft flew over the palace.
The Duchess of Edinburgh appeared awestruck as the planes formed the King's cypher "CR" which stands for Charles Rex and means King Charles in Latin.
After the celebrations, William and Kate took to social media to release images and thanked all those involved. The heartfelt message read: "Thank you to everyone involved in this year's Trooping the Colour. We loved seeing you all!"
What happened at Trooping the Colour?
Over 1,400 parading soldiers, 200 horses and 400 musicians took part in the annual display of military precision, horsemanship and fanfare.
During the ceremony, the King was greeted by a royal salute and carried out an inspection of the troops.
This year, the Welsh Guards' Colour was be trooped. The Foot Guards and the Household Cavalry then marched past His Majesty, and The King's Troop, Royal Horse Artillery, ranked past.
After the ceremony, the King rode back to Buckingham Palace before taking another salute at the palace from a dais.
The event concluded with the royals watching the military flypast from the palace balcony.
The King's official birthday was on 17 June this year, but his actual birthday is 14 November. Find out why Charles has two birthdays.