All On Parade For The King Trooping the Colour to Honour His Birthday -- Guardsmen marching in formation during the colourful Trooping ceremony. Thousands lined the London streets and packed the Horse Guards Parade today to see a glittering display of pageantry - the ceremonial Trooping the Colour in honour of the King's Birthday. The trooping is a special form of guard mounting now reserved for that occasion only. It honours the regiment whose colours are trooped. This year it was the Coldstream Guards, who celebrate their tercentenary. The King, wearing the scarlet uniform and bearskin of the Colonel-in-Chief of the regiment, was cheered all the way as he drove in an open landau from Buckingham Palace to the parade ground, where the scarlet uniforms were seen against a rainbow background of gay summer frocks. On return to the Palace the King and the Royal Family watched a birthday fly-past of 18 Lincoln bombers. Jane 8, 1950. (Photo by Paul Popper, Paul Popper Ltd.).