The Queen's Platinum Jubilee celebrations will draw to a close this afternoon with a colourful street pageant - which royal revellers hope will be capped by a Buckingham Palace appearance by Her Majesty.
The Queen has been forced to miss much of the weekend's events due to mobility issues, but royal fans are hoping to catch a glimpse of the 96-year-old at the finale.
A selection of 200 "national treasures" - including Ed Sheeran, Joe Wicks and Harry Redknapp - will serenade the Queen by belting out the national anthem in The Mall.
Across the country millions of Brits are expected to take part in street parties and picnics on the fourth day of a long Bank Holiday weekend - although the Met Office has warned that storms could spoil the party.
It comes after she received affectionate tributes from the Prince of Wales and national figures during Saturday night's Platinum Party at the Palace that saw Sir Rod Stewart, Diana Ross and Duran Duran perform for thousands.
Follow the Queen's Platinum Jubilee celebrations in our live blog here
And in a comic sketch that delighted the nation, the Queen had tea with Paddington Bear and revealed, like the furry character, she is partial to a marmalade sandwich.
In his personal tribute Charles spoke movingly about the Queen, calling her "Mummy" and described how "you laugh and cry with us and, most importantly, you have been there for us..." in a speech to thousands of spectators in The Mall.
Today millions will gather for patriotic street parties, picnics and barbecues, with more than 85,000 Big Jubilee Lunches being held across the UK.
Coverage begins on BBC One from 1pm with commentary from Clare Balding, while Kirsty Young, AJ Odudu, Anita Rani, Anton Du Beke, Sophie Morgan and Owain Wyn Evans report on street parties across the UK.
The Duchess of Cornwall, patron of the Big Lunch, will join Charles at a flagship feast at The Oval cricket ground in south London, while the Earl and Countess of Wessex will meet people creating the "Long Table" down on The Long Walk leading up to Windsor Castle.
From 2.30pm, some 10,000 people including a cast of 6,000 performers will take part in the 3km carnival procession from Horse Guards, along Whitehall to Admiralty Arch and down The Mall to Buckingham Palace.
The ambitious £15 million pageant is split into four acts: For Queen and Country with a military parade; The Time of Our Lives progressing through seven decades of culture, music and fashion; Let's Celebrate telling the story of the Queen's life in 12 chapters with corgi puppets and carnival creations; and the Happy and Glorious musical spectacle.
Celebrities will travel in decorated open top double decker buses for the decade-by-decade celebrations.
Among the sights will be the Gold State Coach which will feature archival footage of the Queen broadcast at the windows, making it seem as if the monarch is in the carriage.
A peloton of 300 cyclists riding vintage bikes will travel down The Mall led by Sir Chris Hoy, Dame Laura and Sir Jason Kenny.
Stars including Sir David Jason, Sir Cliff Richard, Sandie Shaw, Felicity Kendal and Holly Willoughby will join Ed Sheeran in a mass rendition of God Save The Queen outside Buckingham Palace to bring the festivities to a close.
It is hoped the monarch will make an appearance on the Buckingham Palace balcony to round off the weekend and see the celebrities singing the national anthem.
At 8pm on BBC Two, Kirsty Young looks back at the weekend of celebrations.
In Scotland people will picnic in gardens beneath Edinburgh Castle and enjoy live music.
Those attending the free event in West Princes Street Gardens will also be able to watch the Platinum Jubilee Pageant broadcast live from London, which will be shown on big screens.
The band of HM Royal Marines Scotland and the local Love Music Community Choir will perform at the picnic which will feature live music from 12.30pm followed by the pageant later in the afternoon.
Music from the HM Royal Marines Scotland band will include their Corps of Drums, film music, Scottish melodies and virtuoso soloists.
Edinburgh's Lord Provost Robert Aldridge said: "The Platinum Jubilee is a truly historic event and it was important to find a fitting tribute here in the capital for those who wish to come together and celebrate the occasion.
"In the tradition of Jubilee street parties our big picnic in the gardens invites citizens to come together to enjoy some fantastic local entertainment and music.
"Watching the celebrations on the big screen will be a great way for people to be involved and soak up the atmosphere of this extraordinary day."
There will also be a special Edinburgh Festival Carnival parade just for the occasion.
British Forces Broadcasting Service presenter Mark McKenzie will be master of ceremonies for the afternoon.
He said: "It's a huge honour and I'm delighted to be involved in helping celebrate her majesty's Platinum Jubilee in Edinburgh.
"The programme has a real eclectic feel, capturing not only a flavour of Scotland but the Commonwealth and beyond.
"It's always a thrill hosting with Edinburgh Castle as a backdrop, it will be a day with something for everyone."