Britain's King Charles III wearing the Imperial state Crown carrying the Sovereign's Orb and Sceptre leaves Westminster Abbey after the Coronation.

 LONDON - Thousands of people turned central London red, white and blue on Saturday, with a sea of Union Jack flags lining the streets for the coronation of King Charles III.

While the coronation service was itself a sombre and sober affair, a celebratory atmosphere filled the British capital and beyond, despite wet weather.

From the early hours, people dressed in red, white and blue and clutching union flags lined the streets for the first coronation in Britain for 70 years, which brought an outpouring of joy and unity but also solemn emotion, they said.

Many had brought stools or steps, to be able to see over the crowds, and wore elaborate fancy dress including paper crowns and plastic tiaras. While the service took place within

Westminster Abbey strangers huddled together under umbrellas to watch the ceremony on ipads, or watched on big screens in parks.

Small children were held up to see as the royal family were taken in carriages back towards Buckingham Palace.

On The Mall outside Buckingham Palace, the most fervent royal fanatics got the party started hours before the ceremony began, with some camping out for days to secure a prime spot for the historic event.

As the royal procession passed on the way to Westminster Abbey, a forest of arms rose as people captured images of the king with their mobile phones.

Street vendors joined the hardcore supporters in the clamour to see the monarch's golden coach, with one man bellowing out "God Save the King".

"We've been here since five (am)", said proud fan Alison Marschall, as she showed off her video of the procession.

At Whitehall, the road leading to Westminster Abbey, crowds cheered and waved flags when the carriage with the king and queen passed by.

Emma Cuthbert, 40, said seeing the procession was "brilliant", adding "I've come a long way to see this, so I'll be staying here all day."

Among the early birds on The Mall was Caryl Hall, 55, and her teenage children.

"I'm excited. There's a good vibe, good atmosphere -- friendly, happy, patriotic," said Hall, draped in a flag with a plastic crown on her head.

"It was hard to wake up the teenagers but this is part of history," added the South African, who was standing on a stool to get a good view.

Dave Giddings travelled from Scotland with his wife and son.

"It's being part of the future. It's an important thing," said the 41-year-old, sporting a gold crown and Union Jack sunglasses.

'History' 

Torrential downpours on Friday failed to dampen spirits, with more bad weather forecast throughout Saturday.

Hillary, 72, and her daughter Jo, 47, caught an early train to join the crowds.

"It's living history. He is never going to be the queen (Elizabeth II) but he is our king and today we just want to celebrate," said Hillary, who only gave her first name.

The pair were loaded up with Union Jack hats, flags and picnic chairs, but in true British fashion were worried about the weather forecast.

Many have flown in from abroad, including Christine Wilen, a retired nurse from Niagara Falls in Canada.

"I made the trip for the coronation," the 55-year-old, kitted out in the colours of her native Canada, told AFP.

"I'm very excited to be here, to be part of this history. I've always been a monarchist," she added.

Recent polls indicate waning support for the royals, especially among younger people, but plenty of monarchists of all ages turned out Saturday, including Londoner Caba Mendes, 21.

"It's a great day for the country, I can't wait," he said while holding his phone with a selfie stick for the procession on The Mall.

Helen Rimmer, who travelled from Cumbria, northwest England, on Friday night, secured her spot on Whitehall at 4:45 am.

"It's a very special occasion, especially for our country and the Commonwealth. It's the atmosphere, just everything about it really. It's just a big celebration. It's great."

Sam Mindenhall, a 27-year-old cafe worker from Bristol, south west England, said he thought Charles would balance the tradition of a monarchy that dates back almost 1,000 years with

the modern face of Britain.

"I think a lot of the issues that he cares about are quite important," he said, adding that Charles appeared to be "trying to be more inclusive and bring more people into our nation". Agencies