Allan Little
Special correspondent

Image source, PA Media

That the King has chosen to begin his reign with visits to Edinburgh, Belfast and Cardiff is telling.

It suggests that the future of the Union is at the heart of his concerns.

The early decades of his late mother's reign were characterised by the long, slow contraction of British Imperial power around the world.

He will be alert to the possibility that his own reign could come to be defined by the continuation of that process here - and the eventual dissolution of the United Kingdom itself.

The Queen's children carried out the traditional Vigil of the Princes around the coffin of their late mother in St Giles' Cathedral, Edinburgh, earlier this evening.

The symbolic move sees four people position themselves at each side of the coffin to stand guard for a short time - today's event lasted 10 minutes.

King Charles III took up the role alongside his three siblings, the Princess Royal, the Duke of York and the Earl of Wessex.

Following the Vigil of the Princes, the Queen's coffin will continue to rest at St Giles' Cathedral in Edinburgh until 17:00 BST on Tuesday.

It will be moved from Edinburgh to the city's airport, where it will then be flown to RAF Northolt in west London at 18:00.

The Princess Royal, Princess Anne, will accompany the coffin, as she has since the beginning of its journey from Balmoral.

The coffin is expected to arrive in London at 19:00, and will then travel to Buckingham Palace, where it will be met by King Charles III and Camilla, Queen Consort.

The King and his wife will continue their tour of the nations tomorrow by visiting Belfast, where the monarch will meet Secretary of State for Northern Ireland, Chris Heaton-Harris, as well as other party leaders.

After a meeting with religious leaders, the royal couple will attend a prayer service at St Anne's Cathedral before travelling to London.

You can read about the day's proceedings in more detail here.

About 20,000 people have been waiting in a mile-long queue for several hours to enter St Giles' Cathedral in Edinburgh, where the Queen's coffin lies at rest.

William MacDonald, 63, from Edinburgh, says he was "extremely moved" by the experience of finally getting to pay his respects.

“It was beautiful,” he says. “Everything was done so well. I will never forget it. It was mind-blowing.

“She has been the best Briton ever, along with Winston Churchill.

"I am a bit star-struck.”

Rodney Matthews, a retired Baptist minister and member of Old Saint Paul's, a Scottish Episcopal Church in the heart of Edinburgh, says there was a sense of serenity about the event.

“You were able to move very slowly through, there was no rush at all," he says.

“There’s a moment where you can actually stand there and take it all in, the dignity of the whole place.

“It was very well done, very well organised once you go through security and get that feeling of space.”

Image source, PA Media

After a poignant 10 minutes, the vigil has now come to an end, with the Royal Family returning to their cars to applause from the crowd outside the cathedral.

As we reported earlier, the Queen's four children are performing the traditional Vigil of the Princes around the coffin of their late mother at St Giles' Cathedral.

The symbolic move sees four people - in this case King Charles III, Princess Anne and Princes Andrew and Edward - position themselves at each side of the coffin to stand guard for a short time.

The Princess Royal's appearance makes her the first woman to be part of the vigil, which has until now been carried out by male-only members of the Royal Family.

When the Queen Mother died, her four grandsons carried out the duty - Charles, Andrew, Edward and David Armstrong-Jones, Princess Margaret's only son.

King Charles III and Camilla, Queen Consort, are now arriving at St Giles' Cathedral where they will hold a vigil for the Queen.

Frank Gardner
BBC News, Security Correspondent

Image source, PA Media

We've seen big crowds in Edinburgh today as the Queen lies at rest in St Giles' Cathedral - and yet more are expected once her coffin arrives to London tomorrow.

The primary concern for the police and security services over the coming days is public order rather than a terrorist threat.

The Metropolitan Police is leading on this, working closely with Police Scotland and the security service, MI5. They have rehearsed extensively for this week.

The current UK terror threat level remains at "substantial", meaning a terrorist attack is thought to be likely, but not highly likely or imminent - which would be two levels above where we are now.

The police are not aware of any specific terrorist threat to events marking the death of the Queen and there has been no noticeable increase in chatter amongst extremist groups or individuals.

That said, I’m told "no-one is going to breathe easy until these events are behind us" - and a number of Armed Response Vehicles (ARVs) are parked up in side roads in central London.

A stream of mourners has been queueing in the late summer sunshine to enter St Giles' Cathedral in Edinburgh, where the Queen's coffin lies at rest.

They collected wristbands about a mile away at a station in The Meadows park earlier on, before queueing through the main University of Edinburgh area of the city to reach the cathedral.

Image source, Reuters

Image source, Reuters

Image source, EPA

Image source, Reuters

Image source, PA Media

Coming up, King Charles III will be back at St Giles' Cathedral in Edinburgh to hold a vigil for his late mother.

He'll stand by one corner of the raised platform - or catafalque - that her coffin is resting on. His siblings are expected to position themselves at the other three.

The process - called the Vigil of the Princes - was first carried out in 1936 when King Edward VIII and his three brothers, Princes Albert, Henry and George, stood by the coffin of their late father, King George V.

Since then, it has only been done on one other occasion - at the funeral of the Queen Mother in 2002. The King - who was known then as Prince Charles - was one of the people who stood by on that occasion.

The Queen's coffin is now at rest on a catafalque - a raised platform - in St Giles' Cathedral, Edinburgh.

It was carried in, after the procession down the Royal Mile, by the Royal Regiment of Scotland.

This is the moment some in Edinburgh have been waiting for all day - the chance to view the Queen's coffin and pay their respects.

Wheelchair users have been given priority and have begun entering the cathedral.

Some people have been queueing since before 7am to ensure they get a wristband.

Officers of the King's Body Guard for Scotland are standing guard around the Queen's coffin - King Charles will stand vigil next to it later this evening.

Philip Sim
BBC Scotland political correspondent

Less than a year ago, King Charles was at Holyrood for the royal opening of a new term of parliament.

That day he was by his mother’s side; today he returned as he takes her place as monarch.

He processed into the chamber preceded by the mace gifted to the parliament in 1999 by the Queen, and guards from the Royal Company of Archers.

There was a full house of MSPs - including several who had taken his dress cue by wearing kilts. Among them was Stuart McMillan, the parliament's piper, who played the close of the ceremony as he had done in the past for the Queen.

The public gallery was packed out too, with former first ministers and presiding officers in attendance along with senior figures from the judiciary and clergy.

The speeches were short and fairly solemn, even from parties with republican leanings; this was a day for ceremony, not politics.

Nicola Sturgeon even raised a laugh from the new King with a story of a Corgi chewing through a light cable while she was dining at Balmoral.

And Charles himself pledged to follow his mother’s “inspiring example”, after noting her “deep and abiding bond” with Scotland.

King Charles III gives his reponse to the Scottish Parliament's motion of condolence.

Through all the years of her reign, the Queen, like so many generations of our family before her, found in the hills of this land, and the hearts of its people, a haven and a home, he says.

"My mother felt as I do, the greatest sense of admiration for the Scottish people," he says.

"And it was the greatest comfort for her to know the true affection in which she was held."

Scottish Labour Party leader Anas Sarwar says that first and foremost “the Queen was a mother”.

“I hope it gives you and your family much comfort that we are all grieving the passing of someone who was so special, cherished and loved by us all.”

Sarwar says the Queen reminded him of his own grandmother – “even the way she held her handbag” – and says his six-year-old child was crying after the news of her death because he would never get to meet the Queen.

He ends by wishing King Charles III “a long and happy reign”.

Image source, .

Douglas Ross, the leader of the Scottish Conservative Party, speaks after Sturgeon.

“The Queen seemed as permanent as the stones of Edinburgh Castle,” he said, touting her lengthy reign and describing her as “an anchor to our history”.

He also addressed the new King Charles III, pointing out that he became the first sovereign to accede to the throne while on Scottish soil in more than 400 years.

“I know that people across the country will show you the same support and devotion as they did your late mother,” Ross says.

“Because today we don’t just commemorate the reign of our Queen but also celebrate the life of a woman who many in Scotland knew and loved, who dedicated her life to her country, to duty, and to serving others.”

Sturgeon closes her speech, stating the Queen has been "intrinsic" to Scotland.

"She was present at so many of our iconic moments," she says.

"She was also a true and steadfast friend of the Scottish Parliament," she adds.

"On the day we reconvened in 1999, she allowed the title, Queen Elizabeth, Queen of Scots, to be used," she says, closing the speech with: "Queen Elizabeth, Queen of Scots, we are grateful for her life. May she now rest in peace."

First Minister Nicola Sturgeon recalls how she was nine years old when she first met the Queen.

She visited Irvine, Sturgeon's hometown, in 1979, to open the Magnum Leisure Centre, says Sturgeon.

"I was one of hundreds lining the streets with my mum, and by luck we ended up close to her car as it passed by. Nine-year-old me was absolutely convinced I had caught her eye.

"That nine-year-old girl could not have imagined more than 35 years later, being in the front passenger seat of another car, this time with the Queen at the wheel, driving through the Balmoral estate."

She adds these are memories that she treasures.

After two minutes of silence, Scotland's First Minister Nicola Sturgeon begins her motion of condolence in the Scottish Parliament.

"For people across our country, this is a time of profound sorrow," she says.

"Most of us simply do not remember life without the Queen.

"In an everchanging and often turbulent world, Her Majesty has been our constant, she has been the anchor of our nation."

King Charles III's busy schedule continues, with the monarch now at the Scottish Parliament where a motion of condolence will be heard.

He is joined by his wife Camilla, the Queen Consort.

The motion will provide an opportunity for Members of the Scottish Parliament, MSPs, to reflect on the Queen’s life of "exceptional public service and her close and enduring bond with Scotland", according to the Parliament website, external.

The King will then respond to the motion.