Trooping The Colour is also known as The Queen's birthday parade, and it has marked the Sovereign's special day for over 260 years.
"Today more than 1,400 soldiers will put on a display of military pageantry, with hundreds of Army musicians and around 350 horses," the post continued.
"As Sovereign, The Queen is Head of the Armed Forces. As Princess Elizabeth, she joined the Auxiliary Territorial Service (ATS) in 1945, becoming the first female member of the Royal Family to join the Armed Services as a full-time active member."
The historical throwback was quick to garner plenty of love from royal observers.
"Magnificent and elegant all at once ❤️," one user commented.
"Prince William will do her majesty and the royal family proud during this very special trooping of the colour for the platinum jubilee," another added.
The last time Queen Elizabeth held a Trooping The Colour ceremony at Windsor Castle, it was a low-key "mini" event as a result of the restrictions surrounding the coronavirus pandemic.
Tonight's event, however, will feature much more fanfare as a display of military precision, horsemanship, and finally, the royal family on the Buckingham Palace balcony will set the streets of London alight.
While our living rooms won't compare to the energy over in London, we can still catch Trooping the Colour on Seven and Seven HD tonight from 8:30 to 11:50 pm.