Thousands of spectators have joined the Queen and Duke of Edinburgh at the annual Trooping the Colours parade to mark her 82nd birthday.

Over 1,100 soldiers took part in the military spectacle, which has been performed for decades at Horse Guards Parade in Whitehall.

The Queen and the Duke of Edinburgh arrived at the event by carriage, followed by Prince Charles and the Princess Royal on horseback.

Princes William and Harry arrived in a second carriage with their stepmother, the Duchess of Cornwall.

Other guests included Prime Minister Gordon Brown and his wife Sarah, and Henry Allingham, Europe's oldest man at 112 and one of three known remaining UK survivors of the First World War.

The Queen's actual birthday was on 21 April, but the tradition of two birthdays first started when outdoor events were considered to be unsuitable for monarchs if they were born in winter.

The Colour being paraded on Horse Guards Parade this year was the flag of the 1st Battalion Welsh Guards.

Trooping the Colour originated from traditional preparations for battle. Colours, or flags, were carried, or "trooped", down the ranks so that it could be seen and recognised by the soldiers.

In the 18th century, guards from the Royal palaces assembled daily on Horse Guards Parade to "troop the colours", and in 1748 it was announced that the parade would also mark the Sovereign's official birthday.

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