The ceremonial Trooping the Colour is one of the most colourful and spectacular ceremonial occasions to be seen in London. It takes place on the sovereign's "Official Birthday" early in June each year and is a very popular tourist attraction, open to the public at no cost.

THE ORIGINS OF THE FESTIVAL
Although the Queen was born on 21 April, it has been the custom to celebrate the Sovereign's birthday publicly on a day in the summer for many years. The ceremony of trooping the Colour dates back to the beginning of the 18th century or even earlier, when the colours (flags) of the battalion were carried (or 'trooped') down the ranks so that they could be seen by the soldiers and recognised in future. Since 1748, this parade has also marked the Sovereign's official birthday and, since Edward VII's reign, the Sovereign has taken the salute in person at Trooping the Colour. Traditionally the sovereign has taken the salute mounted (in the Queen's case, riding side-saddle) and wearing the uniform of the Colonel-in-Chief of the regiment whose colour is being "trooped", but in recent years the Queen has bowed to advice and public opinion and now takes the salute from an open horse-drawn carriage.

CUSTOMS AND TRADITIONS
Trooping the Colour is carried out by troops from the Household Division (both Foot Guards and the Household Cavalry) on Horse Guards Parade in Whitehall, London, watched by members of the Royal family, invited guests and members of the public.

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 regimental colour is escorted down the ranks; the Foot Guards and the Household Cavalry then march past the Queen, and the King's Troop, Royal Horse Artillery, parade past.
The Queen rides back to Buckingham Palace at the head of her Guards before taking the salute at Buckingham Palace. The troops then return to barracks.

The event is accompanied by great pageantry and is a very colourful occasion; the streets all along the parade route are lined with crowds, most waving flags, and to get into a good position to see the parade you have to arrive early!

The Queen has taken the salute personally in every year of her reign, except in 1955 when a national rail strike cancelled the event.

The Queen takes part in many other ceremonies, customs and traditions which go back for centuries, including the State Opening of Parliament and the annual distribution of the Royal Maundy. The official "Royal" website can be found here.