Today is the 60th anniversary of Queen Elizabeth's accession to the British throne. While she marked the occasion in modest surroundings at a school in Norfolk, north east England, a saluting battery made their way to London's Hyde Park for an altogether more sonorous tribute. Matt Barringer/CNN
With snow lying heavy underfoot, the King's Troop Royal Horse Artillery trot into position in Hyde Park as part of the annual Accession Day celebrations. Matt Barringer/CNN
The troop, who form a ceremonial unit within the British Army, line up the cannon for a spectacular 41-gun salute. Matt Barringer/CNN
The young gunners kneel by the tradtional First World War 'thirteen pounder' state saluting guns. Matt Barringer/CNN
Despite the blistering cold, spectators gather to watch the salute in the picturesque west London park, home to Kensington Palace -- Princess Diana's former official residence. Matt Barringer/CNN
At the stroke of midday, the gunners commence the salute amidst a plume of smoke and muzzle flash. Matt Barringer/CNN
A royal salute normally comprises 21 guns, increased to 41 if fired from a royal residence. Matt Barringer/CNN
Through thick cannon mist, the gunners prepare to reload as the salute continues. Matt Barringer/CNN
Smoke fills the air and London echoes to the sound of artillery fire as the traditional 41-gun salute come to an end. Matt Barringer/CNN
The ammunition box is carefully cleared away. Matt Barringer/CNN
The sound of pounding guns is replaced by the canter of horse's hoofs as the cavalry step in to collect the guns. Matt Barringer/CNN
Meanwhile, the horses compete with the brass and drums of the marching band. Matt Barringer/CNN
The salute marks the opening salvo of the Queen's Diamond Jubilee festivities -- which will continue around the UK for the next five months. Matt Barringer/CNN
Although primarily a ceremonial unit, with responsibility for firing gun salutes on state occasions, the King's Troop has an operational role as part of the territorial defence of the United Kingdom. Matt Barringer/CNN
The King's Troop are trained as fighting soldiers, six of whom are deployed in Afghanistan at any one time. Matt Barringer/CNN
With their army-issue black boots protecting them from the melting snow underfoot, members of the King's Troop march off the field in file. Matt Barringer/CNN