Mourners from all walks of life have queued to file past the coffin of the Queen as she lay in state in London’s Westminster Hall, paying their final respects to Britain’s longest-reigning monarch before her funeral.

People had waited in line for hours overnight. By mid-morning, the queue stretched about 5km along the south bank of the River Thames, crossing Lambeth Bridge as it neared Westminster Hall.

As King Charles returned to his Highgrove home in the southern English county of Gloucestershire after days of scheduled events, officials expected about 750,000 people to view his mother’s coffin before the lying in state ends at 6.30am on Monday.

Some had travelled from abroad, dropping off bags at nearby hotels to join those moving slowly through Westminster Hall. Mourners included former Prime Minister Theresa May and her husband Philip, who bowed their heads before the coffin as they filed past with members of the public.

Amy Tsai, 24, said she had travelled from Taiwan in May and had taken part in celebrations for the Queen’s jubilee in June in the Scottish capital Edinburgh.

“Now I’m waiting in line to see her lying in state. I’m just shocked,” she said.

Some were there to represent elderly parents, others to witness history and to thank a woman who, having ascended the throne in 1952, was still holding official government meetings just two days before she died.

Queen Elizabeth’s body was brought to London on Tuesday from Edinburgh. She died last Thursday in Balmoral Castle, her Scottish summer home, at the age of 96 after 70 years on the throne.

Her coffin now lies in the centre of Westminster Hall on a purple catafalque placed on a red platform. It was covered by the Royal Standard flag and topped with the Imperial State Crown placed on a cushion, alongside a wreath of flowers.

Soldiers and ‘Beefeaters’ – the red-coated warders usually found guarding the Tower of London – stood vigil with bowed heads.

Among the first inside was Kenneth Taylor, 72, from Reading in central England, who had come with a neighbour and stayed overnight in a tent in the queue.

Tearing up, Taylor said that on seeing the queen lying in state, he felt: “A lump came to my throat.”

“You know, we’ve lost someone special. Her service to this country was really steadfast and unswerving. And she’s probably what I would call the queen of queens.”

The casket had been brought to the hall from Buckingham Palace atop a gun carriage and escorted by soldiers in ceremonial uniforms in a solemn procession on Wednesday.

King Charles, his sons Princes William and Harry and other senior royals walked behind – the two princes united in grief despite a rift between them.

William and his wife Kate will travel to the royal residence of Sandringham in eastern England on Thursday to view floral tributes left there by members of the public.

The full-scale ceremonial procession on the day of the Queen’s funeral is likely to be one of the biggest the country has ever witnessed and will pose a huge security challenge.

Royalty, presidents and other world leaders are expected to attend, although certain nations, including Russia, Afghanistan, and Syria, were not extended invites.

US President Joe Biden, who has also said he will be there, spoke to the new king on Wednesday and “conveyed the great admiration of the American people for the Queen,” the White House said.