Gun salutes have been fired to officially mark the 67th anniversary of the Queen's accession to the throne.
Soldiers from the King's Troop Royal Horse Artillery used six First World War-era 13-pounder field guns to perform a royal salute of 41 shots in London's Green Park.
A 62-gun salute was also delivered by the Honourable Artillery Company at the historic Tower of London in the annual display of British pageantry.
The Queen – the nation's longest-reigning monarch – is away from the capital on her winter break in Sandringham and, as usual, is reflecting on the anniversary of her father's death in private.
The King's Troop Royal Horse Artillery was formed on the wishes of George VI, and the Queen ordered, after her accession, that the title "King's Troop" be retained in memory of her beloved father.
Leading the team for the Troop was Lance Bombardier Grace Gostelow, who broke her neck and risked her life in 2016 stopping a runaway six-horse gun team from ploughing into spectators in Charlton Park.
In 2016 Lance Bombardier Grace Gostelow broke her neck stopping a runaway six horse Gun Team from ploughing into spectators in Charlton Park. Today she's back leading the team for the AccessionGun Salute in Green Park #fearless#thisgirlcan#yourarmy@BritishArmy@KingsTroopRHApic.twitter.com/0daPSQKXoU
— The Army in London (@ArmyInLondon) February 6, 2019
She faced months of recovery and was sent to Headley Court in Epsom, Surrey, for rehabilitation.
"My job's in the Army. I love the Army. I love the Troop and the horses – the horses are the biggest thing for me," she said.
"To get back on board, it's a milestone, to crack on and forget that it happened really."
The bells of Westminster Abbey, the gothic church where the Queen was married and crowned, also rang out to mark Accession Day.
Princess Elizabeth became Queen on February 6 1952, when George VI died in his sleep from lung cancer at Sandringham House.
The new Queen returning to Clarence House with the Duke of Edinburgh after travelling back from Kenya following the death of her father King George VI (PA)
She was just 25 and thousands of miles from home on a Commonwealth tour with the Duke of Edinburgh in Kenya.
Now Elizabeth II is 92 and has ruled for a record-breaking 24,472 days.
She has passed her silver, golden, diamond and sapphire jubilees, and is now just three years away from her platinum 70 years on the throne.
In 2015, when the Queen overtook her ancestor Queen Victoria to become the country's longest-reigning monarch, she admitted bluntly that the royal record was "not one to which I have ever aspired".
She added: "Inevitably, a long life can pass by many milestones. My own is no exception."
The Queen, who usually returns to London soon after her anniversary, will be looking forward to a year in which the royals will welcome another new royal baby – the Duke and Duchess of Sussex's first child.
Here's a look at the Queen in numbers:
1 – Ranking in the list of world's longest-serving current monarchs. She moved to first place after the death of the King of Thailand in 2016.
7 – Great-grandchildren – Savannah and Isla Phillips, Prince George, Princess Charlotte and Prince Louis of Cambridge, Mia and Lena Tindall. Harry and Meghan's baby, due in the spring, will make 8 great-grandchildren.
13 – Prime ministers in office since the start of her reign, from Sir Winston Churchill (1951-55) to Theresa May.
13 – US presidents since the start of her reign.
16 – Countries of which the Queen is monarch – the UK and 15 Commonwealth realms.
21 – Age when she married the Duke of Edinburgh.
25 – Age when she became Queen.
67 – Years on the throne.
71 – Years of marriage to the Duke of Edinburgh.
72% – Proportion of her life that Elizabeth II has spent as Queen by her 67th anniversary on the throne.
599 – Charities, organisations and military regiments of which the Queen is patron or has associations with.
More than 660 – Investitures personally held by the Queen since the start of her reign.
24,472 – Days on the throne on February 6 2019.
50,000 – People the Queen hosts in an average year at banquets, lunches, dinners, receptions and garden parties at Buckingham Palace. The figure for Holyroodhouse in Edinburgh is more than 8,000.
1.45 million – Approximate number of people who have attended a garden party at Buckingham Palace or the Palace of Holyroodhouse since 1952.
More than 3.75 million – Items of correspondence the Queen has received during her reign.
£370 million – The Queen's wealth, according to the Sunday Times' Rich List.