Queen Elizabeth II reaches her 70th anniversary on the throne on Sunday, becoming the first British sovereign in history to achieve such a milestone.
She is expected to spend the day in Sandringham, remembering her father, George VI, on the anniversary of his death.
Accession Day will be officially marked on Monday, when the King’s Troop Royal Horse Artillery fires gun salutes at Green Park And the Tower Of London at 1pm.
Then, celebrations will begin properly in June with a four-day bank holiday and a stacked programme of events across the capital and beyond.
Here's how her record-breaking reign will be marked across London:
Thursday 12 May - Sunday 15 May
Platinum Jubilee Celebration
More than 500 horses and 1,000 performers will take part in a 90-minute show taking the Windsor Castle audience through history from Elizabeth I to present day.
Thursday 2 June
Trooping the Colour
The Queen's traditional Trooping the Colour Parade kicks off four days of historic ceremonies in Horse Guards Parade.
Principal Beacon lit at Buckingham Palace
A beacon will be lit at Buckingham Palace at the same time as those in the capital cities of the 53 other Commonwealth countries. Across the UK, Channel Islands and Isle of Man, 1,500 town and cities will also come together to light beacons at the same time.
Friday 3 June
Service of Thanksgiving
St Paul’s Cathedral will hold a Service of Thanksgiving for the Queen’s reign.
Saturday 4 June
Platinum Party at the Palace
A selection of the world’s greatest entertainers are billed to perform at the concert at Buckingham Palace to celebrate the most significant moments from the Queen’s reign. A ballot for tickets will open in February and it will be shown on the big screen in the Royal Parkland at Sandringham.
Derby at Epsom Downs
The Queen will be joined by members of the royal family for the Epsom Derby.
Sunday 5 June
Platinum Jubilee Pageant
Performers, dancers and musicians will tell the story of the Queen’s reign in London including a ‘River Of Hope’ – made up of 200 silk flags along the Mall.
Big Jubilee Lunch
Street parties are being planned across London and the UK. It will mark the end of the Bank Holiday.
Across the weekend
The Queen’s private estates at Sandringham and Balmoral will also be open for residents and visitors to enjoy the celebrations over the long weekend.