By Sean Coughlan, BBC royal correspondent
Analysis - On the first anniversary of his reign, King Charles will be spending the day "quietly and privately" at Balmoral, with prayers and reflections on the life of his mother, Queen Elizabeth II, who died one year ago.
It is the way the late Queen used to mark the date of her own accession to the throne and the death of her father.
It is a highly appropriate image of continuity, because this year has been much more about stability and reassurance than about change or reform.
Any expectations of a modernising monarch have so far been put on hold.
"It's been surprising in its lack of surprises," said royal commentator, Pauline Maclaran. "People have very quickly become used to him as King."
It had been a "softly, softly" approach, with an emphasis on keeping the ship steady rather than a dramatic new direction, said Maclaran, who is a professor at Royal Holloway, University of London.
"He's been his mother's son this year," added royal historian Anna Whitelock.
It had almost felt like an "unofficial mourning period", with any changes likely to come later in his reign, said Whitelock, professor of the history of modern monarchy at City, University of London.
"It's been a sense of 'not much to see here', which would be seen as a positive," she said.
The rhythm and rituals of the royal year have largely been kept in place. The rotation through big annual events and stately homes has stayed much the same.
"Monarchy is a long game," said royal historian Heather Jones.
A monarch did not have a political cycle where they had to make an immediate impact. Jones believed King Charles had had a quietly successful first year, gaining public acceptance following his mother's long reign, managing the transition and avoiding any disasters.
The checklist of achievements includes a first state visit to Germany, widely seen as a diplomatic success.
And in terms of a change in tone, the Coronation ceremony was a carefully curated display of a more diverse, multi-faith Britain, made up of what the King has called a "community of communities".
There was embarrassment over the Ngozi Fulani race row - in which a black British guest at Buckingham Palace was repeatedly asked where she was "really from". Yet it was resolved swiftly and ended with messages of reconciliation.
Concerns about the King overstepping the mark into political matters have not yet materialised, although he has maintained his interest in environmental campaigns.
The transition to "Queen Camilla" has also happened without ruffling too many feathers, with the halfway house of Queen Consort dropped at the Coronation.
Camilla has carried out one of the more modernising changes, scrapping the archaic sounding "ladies in waiting". She has also continued to campaign over domestic violence, a subject unlikely to have been addressed by previous generations of royals.
But there are still some doubters over her use of the title "Queen". Princess Diana's former private secretary Patrick Jephson said he would have preferred "Princess Consort".
"After all, Prince Philip managed as Prince Consort for all his time as the Queen's husband," Jephson said.
Challenges ahead
In terms of family problems, the fireworks of Prince Harry's memoir, Spare, did not really scorch the King. The book might have rattled the monarchy as an institution, but the King himself was portrayed as an essentially benign and sympathetic figure, if a sometimes puzzled and melancholy one.
Prince Andrew has also mostly kept out of sight this year, despite repeated rumours of ambitions to return to public life.
But there are still questions to be addressed.
"There are issues about the transparency of royal finances, when the public pay a lot of money into this institution. It's a weak point at the moment," said Heather Jones, professor of modern history at University College London.
"They also need to offer some kind of response to the questions that will keep coming up about the legacy of slavery," Prof Jones said. As well as politically significant in the UK, confronting the issue of slavery and the royal family's historical links to it will be particularly important for relations with some of the Commonwealth countries.
But the royal expert believed the biggest challenge for the King was the need to appear socially aware and sensitive to the financial pressures many people were experiencing.
"When people are hungry, history shows it goes badly for monarchies," Jones said. "Monarchy depends on a social consensus."
In that respect the King appeared ahead of the curve, ready to open a new freezer in a food bank as often as cutting the ribbon on a new building.
Professor Whitelock said his Christmas message, which referenced the National Health Service (NHS) and the cost-of-living crisis, was "pretty radical".
But changes in how he runs the monarchy have been less so. Royal spending has not gone down. There is still an "official" birthday, as well as the real one. The long-term future of Buckingham Palace still seems unclear. It is currently under repair but it is open to question whether the King and Queen will ever really live there.
There has been no shift to a small "slimmed down" royal family, although the removal of Prince Harry and Prince Andrew as working royals has arguably achieved that by default.
What do the public make of the new reign?
According to the most recent opinion polls, there is good news for both supporters and opponents of the monarchy. A YouGov poll this week showed the broad picture remains of a clear majority, 62 percent, in support of Britain remaining a monarchy.
But 26 percent wanted an elected head of state, the highest figure in a series of surveys stretching back more than a decade. This was bolstered by growing opposition to the monarchy among the young, with only 30 percent of 18 to 24-year-olds believing the monarchy was "good for Britain".
Anti-monarchy campaign Republic leader Graham Smith said "republicans have the momentum and the monarchy's future has never looked so fragile".
Protests against the monarchy have become a more regular and visible part of royal events. But author and historian Sir Anthony Seldon pointed to the personal popularity of the King, with the same YouGov poll showing 59 percent believed he was doing a good job.
"Few imagined back in September 2022 that King Charles would have had such a good first year," Sir Anthony said.
On walkabouts the crowds do seem to warm to the King, who is a hands-on monarch. He seems energised when he is shaking hands and talking to the public, sometimes appearing to enjoy that more than meeting the long lines of civic worthies on official visits.
This change in body language had been one of the visible differences in the reign, said royal historian Jonathan Spangler, of Manchester Metropolitan University.
There is much less stand-offishness. And Dr Spangler said the King had been good at building a wide network of contacts over the years. "Talking to people helps him inform his ideas," he said.
But can this connection work for young people and those who are feeling less enamoured with the monarchy?
"The Queen was praised for never having an opinion in public. But young people now say, 'If you've got a platform, use it'," Whitelock said.
After Elizabeth author Ed Owens said the challenge for the King as his reign developed was to avoid being on the wrong side of younger generations' sense of social injustice.
There was a generational sense of grievance over issues such as unaffordable housing, student debt and cost of living pressures - and Dr Owens suggested it would be perilous for the monarchy's future to be seen as a symbol of that unfairness.
The King is believed to be planning a big food project in the autumn - in terms of preventing waste and providing better access to good quality food, which could align with concerns about sustainability and food poverty.
But there is another often overlooked factor in the reign of King Charles. No monarch in British history has come to the throne at such a late stage in life. It cannot be easy to be the new broom at the age of 74.
That could be why Prince William has become such an important figure in this reign. Much of the modernising and taking on social problems, such as homelessness, will be through the Prince of Wales. Any shifting in traditions could come through Prince William.
Taking the long view, Patrick Jephson welcomed the fact that the King was not "rushing things".
"I find it very reassuring that his first year has not been marked by some blaze of new initiatives, souped up by the Buckingham Palace press office, and making us all wonder whether he's really a monarch or some sort of politician in a crown," said Jephson, now an author and broadcaster.
But he also warned the royals remained vulnerable to being seen as an "imposition", particularly in tough economic times.
The unending challenge for the King's reign was that this message of value and purpose to the public had to be "daily re-established", he said.
- This story was first published by the BBC.