The King, who attended horseback Trooping the Colour in 2022 for the last time as Prince of Wales, is turning 75 this coming November.
He is known to be a skilled horserider, having played polo for decades.
Horseback, His Majesty will take the salute as colonel in chief of the seven regiments of the Household Division during the event on Horse Guards Parade.
Another key tradition to be revived for the first time in 30 decades is the presence at the parade of every regiment of the Household Division.
The military event today involves more than 1400 parading soldiers, 200 horses and 400 musicians in a procession taking place from Buckingham Palace to Horse Guards Parade. The much-anticipated event will kick off at 10am.
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