Prince William was seen carrying out the final preparations for the upcoming major royal event over the weekend in sweltering temperatures.
Thousands of keen fans gathered at Horse Guards Parade in Central London to watch him complete The Colonel's Review ahead of Trooping the Colour during the King's Birthday Parade this Saturday.
The ceremony involved hundreds of horses and soldiers carrying out complex battlefield drill manoeuvres to military music.
William inspected his troops on horseback whilst wearing a red dress uniform and bearskin cap for the first time as Colonel of the Welsh Guards, the Mirror reports.
However, it seems the Prince of Wales made one small yet touching change to his uniform which he has made to others too.
The shoulder decoration on the jacket, which is known as the epaulettes, now feature the cyphers of both the late Queen as well as the new one for his father King Charles.
Those who are appointed an aide-de-camp to the monarch are allowed to wear the insignia, with William carrying out the honourable position to his father and beloved grandmother.
He first sported both cyphers on the shoulder of his RAF uniform last month at Windsor Castle while carrying out an investiture ceremony.
During the Trooping rehearsals, the temperatures skyrocketed to 28C with the baking heat proving to be too much for some as the Prince later thanked those who had taken part on Twitter.
Throughout the day, at least three soldiers fainted and were taken off on stretchers while two more were helped up off the parade ground.
One member of the Massed Bands of the Household Division got back up to his feet after collapsing and was greeted with a cheering round of applause from the audience.
He appeared to try and carry on playing his instrument but was swiftly escorted by medical staff.
The Prince of Wales acknowledged the "difficult conditions" in a gratitude tweet that he signed with his first initial.
He wrote: “A big thank you to every solider (sic) 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 Colonel's Review is the final evaluation of the Household Division before the soldiers and horses parade for the monarch during Trooping the Colour on June 17 in honour of Charles' birthday.
This year, it is the Welsh Guards' turn - the King's former division - to Troop their Colour.
Preparations for the special ceremony began even before King Charles' Coronation with all seven regiments of the Household Division taking part, including the five regiments of the foot guards – Grenadier, Coldstream, Scots, Irish and Welsh – and two mounted regiments – the Household Cavalry Mounted Regiment and The King’s Troop Royal Horse Artillery.
The annual event has taken place on the British sovereign's birthday for over 260 years.
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