Queen Elizabeth II, wearing the uniform of Colonel in Chief of the Coldstream Guards, rides police horse Winston as she leads the procession back to Buckingham Palace after the Trooping the Colour ceremony, followed by Prince Philip, Duke of Edinburgh (left) and Prince Henry, Duke of Gloucester (1900-1974), London, June 10th 1954. (Photo by Paul Popper/Popperfoto via Getty Images/Getty Images)
