Queen Elizabeth II will be laid to rest on Monday, after a state funeral attended by leaders from around the world and a historic last ceremonial journey through the packed streets of London.

After queuing all night, the final members of the public filed through parliament's cavernous Westminster Hall to see the queen's coffin lying in state before the doors closed at 6:30 am (0530 GMT).

Chrissy Heerey, a serving member of the Royal Air Force who joined the marathon queue twice, was the last person through the doors and described the experience as "amazing".

"When they came to me and said, 'right, you're the last person', I said, really?!" she told AFP, before heading off to join the crowds for the coffin's procession through central London.

"A long day but very well worth it. It's nothing compared to what the queen has done for the country."

The longest-serving monarch in British history died aged 96 at Balmoral, her Scottish Highland retreat, on September 8 after a year of declining health.

She was succeeded by her 73-year-old eldest son, King Charles III, who late Sunday said he and his wife, Queen Consort Camilla, had been "deeply touched" by the public's flood of messages.

"As we all prepare to say our last farewell, I wanted simply to take this opportunity to say thank you," he said.

- 'She was my boss' -

Britain last held a state funeral in 1965 for the country's wartime prime minister Winston Churchill.

Then, the cranes that once unloaded the spoils of Britain's vast empire that Elizabeth inherited were lowered in respect as his coffin was borne up the River Thames by barge.

In the six decades since, Britain's global reach has been much diminished and its place in the modern world has become less certain.

But the country will still dig deep into its centuries of tradition to honor the only monarch that most Britons have ever known.

Many people have camped out for days to witness the elaborate spectacle of pageantry and to pay their final respects.

Auto engineer Jamie Page, a 41-year-old former soldier, stood on Whitehall to observe the procession after the funeral, wearing his military medals from service in the Iraq war.

"Sixteen years old, I swore an oath of allegiance to the queen. She's been my boss. She means everything, she was like a gift from God," he said.

But on Charles, the oldest person yet to ascend the British throne, Page added: "Who knows, time will tell."

Royal Navy sailors will haul the flag-draped coffin, topped with the majestic Imperial State Crown, on a gun carriage from Westminster Hall to the adjacent abbey.

The funeral starts at 1000 GMT. After just under an hour, a bugler will play The Last Post, before two minutes of silence and the reworded national anthem, "God Save the King".

- Biden's tribute -

Former Archbishop of York John Sentamu said the queen, who headed the Protestant Church of England founded by king Henry VIII in the 16th century, did not want a "boring" send-off.

"You're going to be lifted to glory as you hear the service," he told BBC television.

Afterwards, the coffin will be taken west by road to Windsor Castle, with many thousands expected to line the route.

She will be buried alongside her father king George VI, her mother queen Elizabeth the queen mother and sister princess Margaret, reuniting in death the family who once called themselves "us four".

The coffin of her husband, Prince Philip, who died last year aged 99, will also be transferred to lie alongside her.

Elizabeth's funeral could not be more different from Philip's at St George's Chapel, Windsor, in April last year.

Coronavirus restrictions limited mourners to just 30, led by the queen, a solitary figure in mourning black and a matching facemask.

But now, more than 2,000 people, including heads of state from US President Joe Biden to Japan's reclusive Emperor Naruhito, will pack Westminster Abbey, the imposing location for royal coronations, marriages and funerals for more than 1,000 years.

"All the people of the United Kingdom: our hearts go out to you, and you were fortunate to have had her for 70 years; we all were. The world is better for her," Biden said after signing a book of condolence.

Charles will lead mourners, alongside his three siblings and his heir, Prince William.

- 'Out of place' -

In the abbey pews will also be Liz Truss, whom the queen appointed as the 15th British prime minister of her reign just two days before her death.

All of Truss's living predecessors will be there too, plus her counterparts and representatives from the 14 Commonwealth countries outside Britain where Charles is also head of state.

Whether they remain constitutional monarchies or become republics is likely to be the defining feature of Charles's reign.

The queen's death has prompted deep reflection about the Britain she reigned over, the legacy of its past, its present state and what the future might hold, as well as the values of lifelong service and duty she came to represent during her 70-year reign.

Select members of the public won invitations to the abbey for the funeral after outstanding service to the community.

Among them was lawyer Pranav Bhanot, 34, who gave free legal advice and delivered meals during the Covid pandemic.

"I feel completely out of place because all the headlines are saying there are going to be world leaders and presidents," he said, having first dismissed the call from a government official as a hoax.

"But it will give me a really nice opportunity to pay my respects to someone I hugely admired."

Hundreds of thousands of people are estimated to have queued, sometimes for up to 25 hours and overnight, to file past the queen's coffin since it was taken to lie in state last Wednesday.

Some 6,000 military personnel have been drafted in to take part in the solemn procession to and from the abbey, on the route to Windsor and the committal service at St George's Chapel.

- Big Ben tolls -

After the abbey service, Charles and other senior royals will again follow in procession past hushed crowds to a waiting hearse and the final journey to Windsor.

Throughout, Big Ben, the giant bell atop the Elizabeth Tower at one end of the Houses of Parliament, will toll and guns will fire at one-minute intervals.

A vast television audience is expected to watch the funeral worldwide and live online, in a sign of the enduring fascination with the woman once described as "the last global monarch".

But those lining the streets of London -- already jammed at sunrise on Monday -- said they had to bear witness.

"I want to take part in history," said Jack Davies, 14, camped out for the procession with his parents at Hyde Park Corner, where the coffin will be transferred from the gun carriage for the drive to Windsor.

"I will talk about this moment to my children. I'll say: 'I was there!'"
At Windsor, the queen's crown, orb and scepter will be removed and placed on the altar.

The most senior officer of the royal household, the lord chamberlain, breaks his "wand of office" and places it on the coffin, symbolizing the end of her reign.

The lead-lined oak casket, draped with the queen's colors, will then be lowered into the Royal Vault as a lone bagpiper plays a lament.

A private interment ceremony will take place at the adjoining King George VI Memorial Chapel at 1830 GMT.