Millions of people across the UK have marked the royal wedding with street parties, picnics and other festivities.
St Andrews, the Fife town where Prince William and Kate Middleton met, hosted a breakfast for 1,500 people and Downing Street held an outdoor party.
The Westminster Abbey service was shown on big screens in squares, pubs and churches, including in the bride's home village of Bucklebury, Berkshire.
There were 21 arrests at an unofficial party in Glasgow's Kelvingrove Park.
Strathclyde police said most of the arrests were for disorderly behaviour and drunkenness. One police officer was hurt.
In all, there were more than 5,500 applications for street closures to hold events.
A wedding breakfast was held in the hamlet of Chapel Row where the Middletons live, and Bucklebury Farm Park staged a day of celebrations culminating in a proms-style fanfare.
Later, about 100 charity workers and local children were invited to the party in Downing Street, where they celebrated with Prime Minister David Cameron and his family.
In Southampton's Guildhall Square several thousand people turned out for a party laid on by the city council and were encouraged to dress in red, white and blue.
They included Michaela Coutakis, 45, who said: "We came today because it's an important national occasion.
"We're not royalists but it's bringing the country together and it's quite exciting really. We will remember this when we're old and grey and we can say we came down to the square to watch Kate and William get married."
Hundreds of revellers held a fancy dress party on the restored £39m Grand Pier in Weston-super-Mare, Somerset.
In Cornwall, which has strong ties with the Prince of Wales, there were 30 applications for road closures so festivities could be held.
And in Tetbury, Gloucestershire - the closest town to Highgrove House, Charles's family home - people enjoyed picnics. Gloucester Cathedral showed the wedding on a giant screen, and parties took place in the city and in nearby Cheltenham.
A mass picnic also took place along the High Street of Alcester, in Warwickshire and street parties were held in Lavenham and Foxearth in Suffolk and Wells-next-to-the-Sea in Norfolk.
In Eastbourne, East Sussex, hundreds turned up around a huge screen in Princes Park.
In Leeds, where Kate Middleton's father Michael was born, celebrations took place across the city, and York also opted for a fancy dress event.
A number of street took place in Sheffield, with the focus in the city centre at Devonshire Green.
People in Hull are also joining the celebrations, with six street-party applications approved in the city, contrary to reports a few weeks ago saying no-one had applied.
The Marple Bridge Association in Cheshire, which has been planning its town centre party since Christmas, sold 800 tickets.
Almost 250 street parties were being held across Wales, with Cardiff leading the way with more than 50.
On Anglesey, where William and Kate will live, about 2,000 people watched the ceremony on a giant TV screen at the island's agricultural showground. And a beach party took place in the evening.
In Londonderry, royal fans dressed in full wedding attire for breakfasts in community centres. Events also took place in Belfast, Newtownards, and Templepatrick.
In London, big screens were erected in Hyde Park where a crowd of thousands cheered as William and Kate exchanged their vows and there were similar scenes in Trafalgar Square.
Across the capital, there were more than 800 street parties, the Local Government Association said.
Elaine Lowe, 22, was among the revellers to turn up in Manchester city centre where the wedding was shown on a big screen.
"The rain has held off, the sun is out, and we are all having a great day," she said.
"Kate looks stunning and her wedding dress is fabulous. What's not to like about today?"
In Scotland, visitors at royal residence Balmoral Castle watched the ceremony on six big screens.
Hundreds brought picnics and drank champagne as they sat on the lawn outside. The royal couple have enjoyed several breaks at Prince of Wales' home on the estate.
Meanwhile, the breakfast event in St Andrews was televised worldwide.
Elsewhere in the town, John Montgomery, 44, from the Tayport area, said: "St Andrews feels responsible for all of this.
"The atmosphere's fantastic here. It's amazing really for a small Scottish town to have two billion people around the world watching it."
There were 16 street parties held in Edinburgh, including one in Broughton Street for 250 guests.
Republican demonstrations were held in city's Royal Mile, and a large unofficial party in Glasgow was criticised by the local council.
"Not The Royal Wedding Party" events were held in Bristol and Hebden Bridge in West Yorkshire and campaign group Republic hosted a similarly-themed street party in central London.