The Sovereign's birthday is officially celebrated by the ceremony of Trooping the Colour on a Saturday in June.
In 2013 Trooping the Colour (which is also known as The Queen's Birthday Parade) will be held on 15 June.
The tradition of Trooping the Colour:
Although The Queen was born on 21 April, it has long been the tradition to celebrate the Sovereign's birthday publicly on a day in the summer, when good weather is more likely.
Trooping the Colour is carried out by fully trained and operational troops from the Household Division (Foot Guards and Household Cavalry) on Horse Guards Parade in Whitehall, watched by members of the Royal Family, invited guests and members of the public.
View BBC archive footage of The Queen (then Princess Elizabeth) taking the salute for the first time in 1951:
This military ceremony dates back to the early eighteenth century or earlier, when the colours (flags) of the battalion were carried (or 'trooped') down the ranks so that they could be seen and recognised by the soldiers.
View footage of Major Nana Twumasi-Ankrah, an officer in the Household Cavalry Mounted Regiment, talking about taking part in the parade:
Since 1748, this parade has also marked the Sovereign's official birthday. From the reign of Edward VII onwards, the Sovereign has taken the salute in person at Trooping the Colour.
During the ceremony, The Queen is greeted by a Royal salute and carries out an inspection of the troops.
After the massed bands have performed a musical 'troop', the escorted Regimental Colour is carried down the ranks.
The Foot Guards and the Household Cavalry then march past Her Majesty, and The King's Troop, Royal Horse Artillery, rank past.
The Queen rides in a carriage back to Buckingham Palace at the head of her Guards, before taking the salute at the Palace from a dais. The troops then return to barracks.
Her Majesty then joins other members of the Royal Family on the palace balcony for a fly-past by the Royal Air Force.
The Queen has attended Trooping the Colour every year of her reign, except in 1955 when a national rail strike cancelled the event.
View footage of Trooping the Colour 1986:
How to watch:
The processions can be seen from from the Mall. Events begin at approximately 10.00am, with the fly-past at 1.00pm.
The parade is also broadcast live on the BBC in the UK.
Tickets for seated stands around Horse Guards Parade are allocated by ballot in March. Applications should be made in January or February only to:
Brigade Major
HQ Household Division
Horse Guards
Whitehall
London
SW1A 2AX
A rehearsal (known as The Colonel's Review) usually takes place a week before the actual Birthday Parade.
Members of the public wishing to watch are advised to stand on The Mall or on the edge of St James's Park overlooking Horse Guards (their view may be somewhat obscured by troops in this position) from 9.00am.
