The funeral of Queen Elizabeth II

Monday's funeral is one of the largest diplomatic occasions this century.

World leaders, politicians, public figures and European royals, as well as more than 500 dignitaries from around the world, have descended on London to pay their last respects to Britain’s longest-reigning monarch.

No official guest list was released, but many leaders have confirmed their attendance. The doors to Westminster Abbey open at 8 a.m. local time (3 a.m. ET), when it will start to become clear who is and isn't present.

Syria, Venezuela and Afghanistan are three of the countries that haven’t been asked to send a representative, according to Britain’s PA Media news agency.

Representatives from North Korea and Nicaragua have been invited “only at ambassadorial level,” PA added.

Leaders and officials from Russia, Belarus and Myanmar will also be absent. Diplomatic relations between the UK and Russia have all but collapsed since Russia’s invasion of Ukraine.

Read more about the guest list here.

Queen Elizabeth II's lying-in-state has come to an end, after a four-and-a-half-day period that saw huge crowds queue through London for several hours to see the monarch's coffin.

The doors to Westminster Hall, where the Queen's coffin was displayed to the public, shut at 6:30 a.m. (1:30 a.m. ET) ahead of her funeral.

Thousands of people waited patiently to see her in recent days. "The Queue," which stretched for miles along the River Thames towards east London, became a national phenomenon and one of the enduring images of Elizabeth's passing.

Waiting times of more than 12 hours were recorded on several occasions and the entrance to the queue was briefly paused when it reached capacity.

"I am not particularly monarchist or royalist, but I wanted to join for the historical aspect, just to see what it's all about, see everyone coming together," added Alice Hickson, a student, while standing near the end of The Queue near Tower Bridge.

On Saturday, King Charles III and Prince William visited queuers to thank them for their efforts.

Hear more from people who made the journey to say goodbye to the Queen.

London police chiefs and medics are bracing themselves for a security nightmare at the Queen’s funeral on Monday as they balance the need to protect the world’s top leaders and dignitaries with the desire among many to mourn their much-loved monarch.

Some have compared the event in scale to the London Olympics, but in truth the state funeral — the first in Britain since Winston Churchill died in 1965 — is likely to dwarf the 2012 sporting extravaganza.

Codenamed “Operation London Bridge,” arrangements for Britain’s longest-serving monarch have been carefully pored over for years by the many agencies involved, with the Queen herself signing off on every detail before her death.

The three police forces which operate in the British capital — the Metropolitan Police, the City of London Police and British Transport Police — initiated their well-rehearsed plans across London as soon as the death of Elizabeth II was announced on September 8.

The funeral will be the “largest single policing event” that London’s Metropolitan Police force has undertaken, its Deputy Assistant Commissioner Stuart Cundy told reporters Friday.

Read more about the plans here.

Monday is a Bank Holiday across the UK, with millions of people being given the chance to watch the Queen's funeral.

It marks the culmination of a mourning period that has seen Britain gradually grind towards a standstill.

Sporting fixtures and cultural events have been almost entirely suspended on Monday, while museums, banks, businesses, shops and schools are shut.

But while those closures were mostly anticipated following the demise of a monarch whose reign lasted seven decades, others have caused more serious consequences — leaving some Brits mystified and angry.

Non-urgent hospital appointments across the country have been pushed back due to staffing shortfalls, adding to an already unprecedented waiting list for health care in Britain. Holidaymakers have seen their accommodation plans torn up, travelers are warned that flights will be disrupted to avoid noise over London, and funerals and food banks are braced for disturbances.

The confusion reflects a country that has wrestled with how best to honor the Queen. Despite decades of planning for Elizabeth II’s passing, the government has declined to issue firm guidance on what should and should not go ahead during the period of national mourning, leaving many decisions up to providers.

Read our full story here.

The meticulously planned arrangements for the Queen's funeral are set to be a fitting farewell to Britain’s longest-reigning monarch.

Speaking on behalf of the many agencies and departments involved in the funeral, the Earl Marshal, the Duke of Norfolk, said orchestrating the event was “both humbling and daunting.”

He added that it aimed to “unite people across the globe and resonate with people of all faiths, whilst fulfilling Her Majesty and her family’s wishes to pay a fitting tribute to an extraordinary reign.”

Here's a rundown of what we're expecting:

Following the state funeral, the coffin will be conveyed from the hall to Wellington Arch — again with King Charles III leading some members of the royal family behind on foot, while Camilla, the Queen Consort and others follow by car — before making its final journey out of London to Windsor.

Follow the Queen's final journey with CNN's interactive procession map here.

Few people alive remember a time before Queen Elizabeth II.

Her seven-decade reign began in the aftermath of World War II; it persevered through the last throes of Britain’s empire, the insecurity of the Cold War and the dawn of a new millennium, providing a counterweight to the relentless pace of change.

For each of those 70 years, the Queen remained the central fixture in Britain’s collective psyche. Her death, at the age of 96, plunged the country into mourning and an unfamiliar new age.

But on Monday, the nation will say its final goodbye. Britain has ground to a halt for Elizabeth II’s state funeral, expected to be one of the most-viewed events in recent history. 

Crowds will line the streets of London to glimpse the procession, and leaders from countries in every part of the world have descended on the British capital.

The first state funeral in Britain since Winston Churchill’s death in 1965, Monday marks the climax of a lengthy mourning period that has seen Britons turn out in droves to join commemorations for Elizabeth. Thousands queued for several hours to see her lying-in-state, and memorial events were held in towns, cities and villages across the country.

King Charles III, Elizabeth’s son and heir who assumed the throne amid a wave of national mourning, will be joined by the rest of the royal family at Westminster Abbey as he pays respects to his mother later. 

After the service, the Queen will undertake her final journey as her coffin is driven to Windsor and the late monarch is privately buried — the end of a somber period of transition, and the last act of Britain’s long and momentous second Elizabethan age.

The state funeral begins at 11 a.m. (6 a.m. ET).

Stay with us as we take you through this historic moment for the British royal family and the nation.