Trooping The Colour - A close-up of Princess Elizabeth arriving back at the Palace after the ceremony this morning. She was wearing a dark blue habit with Grenadier jacket and dark blue cap with the Guards emblem, and was riding side-saddle for the first at a public-ceremony. Today, in celebration of the King's birthday, the ceremony of Trooping the Colour took place on the horse guards palace. The parade, which dates from the 18th century, has not been held since before the war,when, with the guards resplendent in full dress uniform, it was one of London's most colourful ceremonies. June 12, 1947.