Next Saturday, 16 June, marks King Charles' first Trooping the Colour, and his eldest son, Prince William, took on an important preparatory role at the weekend.
The week before the monarch's birthday parade, the Prince of Wales carried out the Colonel's Review at Horse Guards Parade in his role as Colonel of the Welsh Guards.
When he carried out the inspection last year, the insignia on his collar was that of the Irish Guards, as they had been selected for the honour, but this year, he wore the leek symbol of the Welsh Guards and decorated his bearskin hat with their white and green plume.
The Prince also wore four medals, one of which appeared to be from the late Queen's Platinum Jubilee, as opposed to last year's two. The Colonel's Review is the final rehearsal of the parade before it is witnessed by the King.
The Prince and fellow participants battled high temperatures in London on the day, with several guards fainting. This prompted William to later tweet a personal message, which read: "A big thank you to every soldier who took part in the Colonel's Review this morning in the heat. Difficult conditions but you all did a really good job. Thank you. W."
The Prince thanked soldiers for their hard work
What is Trooping the Colour?
Over 1,400 parading soldiers, 200 horses and 400 musicians come together each June in a great display of military precision, horsemanship and fanfare to mark the monarch's official birthday.
The streets are lined with crowds waving flags as the parade moves from Buckingham Palace and down The Mall to Horse Guard's Parade, alongside members of the royal family on horseback and in carriages.
This year, things will be a little different as it will be Charles's first Trooping the Colour of his reign.
The tradition started in 1748 with George II, who was born in chilly November. Instead of risking his subjects catching a cold, he combined his birthday celebration with the annual spring parade known as Trooping the Colour.
'Colours' refers to the flags that represent the different regiments in the British Army. The army used these flags so that soldiers could spot their unit on the battlefield. 'Trooping', meanwhile, refers to the marching up and down of the troops.
Trooping the Colour therefore refers to when the flags of the different regiments are displayed. Each year, a different regiment is chosen to 'troop' their 'colour'.
Who attends Trooping the Colour?
After the ceremony, the royals gather on the Buckingham Palace balcony to watch the flypast. While we have seen extended members of the family on the balcony in previous years, it's likely that King Charles and Queen Camilla will only be joined by working members of the royal family on this occasion, keeping in line with last year's event and the recent coronation.
Therefore, we can expect to see the likes of the Prince and Princess of Wales and their three children, Prince George, Princess Charlotte and Prince Louis, and the Duke and Duchess of Edinburgh, and their kids, Lady Louise Windsor, and James, Earl of Wessex.
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