The day of splendour and formality will feature customs dating back more than 1,000 years. Here is how we expect it to unfold.
The formal celebrations will begin with a procession from Buckingham Palace to Westminster Abbey and viewing areas along the route opened at 06:00.
Public access to sites along The Mall and Whitehall are on a first-come, first-served basis, with people directed to official screening sites in Hyde Park, Green Park and St James’s Park once they are full.
Stands for almost 4,000 invited guests, including armed forces veterans and NHS and social care staff, have been erected outside Buckingham Palace.
Heads of state and representatives of overseas governments will arrive from 09:30, foreign royals from 10:25 and members of the British Royal Family from 10:35.
As the congregation gathers in the abbey, armed forces personnel taking part in the procession to the abbey will begin to gather in the Buckingham Palace grounds and on Whitehall.
Outside the gates, a Guard of Honour, comprising about 160 members of the three armed services will get into position, with another 1,000 personnel lining the route.
The procession will set off from Buckingham Palace at 10:20 BST (05:20 EDT) moving along The Mall to Trafalgar Square, then down Whitehall and Parliament Street before turning into Parliament Square and Broad Sanctuary to reach the Great West Door of Westminster Abbey.
In a break from tradition, King Charles and Queen Consort Camilla will be in the Diamond Jubilee State Coach rather than the older, more uncomfortable, Gold State Coach.
Westminster Abbey arrival
The King will enter the abbey through the Great West Door at 10:53 wearing a red velvet robe of state. Underneath he is likely to be wearing a military uniform rather than the more traditional breeches and silk stockings worn by kings before him.
Before the King arrives, there will be processions in the abbey involving faith leaders and representatives, and representatives from some Commonwealth countries who will carry the flags of their country and be accompanied by the governors general and prime ministers. These will include UK Prime Minister Rishi Sunak, who will also give a reading later in the service.
The ceremony is due to begin at 11:00 and will be punctuated with music selected by the King, with 12 newly commissioned pieces, including one by Andrew Lloyd Webber, and Greek Orthodox music in memory of the King’s father, Prince Philip.
The King’s grandson, Prince George, will be among the pages, alongside Camilla’s grandchildren, Lola, Eliza, Gus, Louis and Freddy.
Some of those who walk ahead of the King through the abbey before the service will carry the regalia, with most items placed on the altar until needed in the ceremony.
What is the regalia?
The UK is, according to the Royal Family website, the only European country that still uses regalia – the symbols of royalty like the crown, orb and sceptres – in coronations.
The individual objects symbolise different aspects of the service and responsibilities of the monarch.
Charles will be presented with the Sovereign’s Orb, the Sovereign’s Sceptre with Cross, and the Sovereign’s Sceptre with Dove and other items at key moments in the ceremony.
And Camilla will be presented with the Queen Consort’s Rod with Dove and the Queen Consort’s Sceptre with Cross – mirroring the King’s sceptres.
There are several stages to the service, which is expected to last a little under two hours.
For the first time members of the public will be invited to pledge their allegiance to the King, in a part of the service organisers are calling the “chorus of millions”. In another departure from tradition, female clergy will play a prominent role and religious leaders from other faiths will have an active part.
Stage one: The recognition
King Charles will be presented to “the people” – a tradition dating back to Anglo-Saxon times. Standing beside the 700-year-old Coronation Chair, the King will turn to face the four sides of the abbey and be proclaimed the “undoubted King” before the congregation is asked to show their homage and service.
Archbishop of Canterbury Justin Welby will make the first declaration but, for the first time, the subsequent declarations will be made by the Lady of the Garter and the Lady of the Thistle – representing the oldest orders of chivalry in England and Scotland respectively – and a George Cross holder from the armed forces.
The congregation will shout “God Save the King!” and trumpets will sound after each recognition.
The Coronation Chair, also known as St Edward’s Chair or King Edward’s Chair, is believed to be the oldest piece of furniture in the UK still used for its original purpose. A total of 26 monarchs have been crowned in it.
It was originally made by order of England’s King Edward I to enclose the Stone of Destiny, which had been taken from near Scone in Scotland.
The stone – an ancient symbol of Scotland’s monarchy – was returned to Scotland in 1996 but has been transferred back to London for use in the service.
During the Coronation, the oak chair is placed in the centre of the historic medieval mosaic floor known as the “Cosmati pavement”, in front of and facing the high altar, to emphasise the religious nature of the ceremony.
Stage two: The oath
Just before the oath, the Archbishop of Canterbury will acknowledge the multiple faiths observed in the UK by saying the Church of England “will seek to foster an environment in which people of all faiths may live freely”.
The archbishop will then administer the Coronation Oath – a legal requirement. He will ask King Charles to confirm that he will uphold the law and the Church of England during his reign, and the King will place his hand on the Holy Gospel and pledge to “perform and keep” those promises.
The King will also take a second oath – the Accession Declaration Oath – stating that he is a “faithful Protestant”.
Stage three: The anointing
The King’s ceremonial robe will be removed and he will sit in the Coronation Chair to be anointed, emphasising the spiritual status of the sovereign who is also the head of the Church of England.
The archbishop will pour special oil from the Ampulla – a gold flask – on to the Coronation Spoon before anointing the King in the form of a cross on his head, breast and hands.
The Ampulla was made for Charles II’s coronation, but its shape harks back to an earlier version and a legend that the Virgin Mary appeared to St Thomas a Becket in the 12th Century and gave him a golden eagle from which future kings of England would be anointed.
The Coronation Spoon is much older, having survived Oliver Cromwell’s destruction of the regalia after the English Civil War.
Then at 12:01 the archbishop will place St Edward’s Crown on the King’s head and the abbey bells will ring for two minutes, trumpets will sound and gun salutes will be fired across the UK.
A 62-round salute will be fired at the Tower of London, with a six-gun salvo at Horse Guards Parade. Twenty-one rounds will be fired at a further 11 locations around the UK, including Edinburgh, Cardiff and Belfast, and on deployed Royal Navy ships.
Stage five: The enthronement
The final part of the ceremony will see the King take the throne.
Traditionally, a succession of royals and peers would then have paid homage by kneeling before the new king, swearing allegiance and kissing his right hand.
However, Prince William will be the only Royal Duke to kneel and pay homage to King Charles.
And instead of peers, for the first time the archbishop will invite people in the abbey, and those watching and listening at home, to pledge allegiance in what is called a “new and significant moment in the tradition of the coronation” by organisers.
The Queen Consort
After the homage, Queen Camilla will be anointed, crowned and enthroned in a simpler ceremony – although she will not have to take an oath.
She will be crowned with Queen Mary’s Crown – originally made for Queen Mary’s coronation alongside George V – but it is being modified to remove some of the arches and reset with the Cullinan III, IV and V diamonds.
The final part of the service will see the King and Queen taking Holy Communion – the principal act of worship of the Christian church.
The King and Queen Consort will leave their thrones and enter St Edward’s Chapel behind the high altar – here Charles will remove St Edward’s Crown and put on the Imperial State Crown before joining the procession out of the abbey as the national anthem is played.
The King and Queen Consort will then return to Buckingham Palace along the reverse of the route by which they came, this time travelling in the 260-year-old Gold State Coach that has been used in every coronation since William IV’s.
The Princess Royal will be among those riding behind the coach, while the Prince and Princess of Wales and their three children, princes George and Louis and Princess Charlotte, will be among the royals in the three carriages and first car following.
They will be joined by representatives from 39 Commonwealth countries and the British Overseas Territories.
Most will march ahead of the King along the 1.42 miles (2.29km) route and, as the front of the procession reaches the palace, the back will still be at Downing Street.
The King and Queen Consort will arrive at the palace at about 13:30 and head to the west terrace where they will receive a Royal Salute and three cheers from military personnel who were on parade.
Buckingham Palace fly-past
It has become customary since the coronation of Edward VII in 1902 for the new monarch to greet the crowds in The Mall from the Buckingham Palace balcony – the Queen was joined by her mother, children and sister among other royals as she watched a fly-past involving hundreds of planes in 1953.
Buckingham Palace has confirmed that King Charles and Queen Camilla will continue the tradition and appear shortly before 14:30 – although which other members of the Royal Family will be involved has not yet been confirmed.
Those there will witness the end of the day’s public celebrations at 14:30, with a six-minute fly-past planned involving members of the Army, Royal Navy and Royal Air Force and culminating in a display by the Red Arrows.
Written and produced by Chris Clayton, design by Lilly Huynh and Zoe Bartholomew, illustration by Jenny Law
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