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Princess Eugenie is elegant in a black as she leaves Clarence House

Princess Eugenie and Princess Beatrice have left Clarence House for the Queen’s procession to Westminster Hall.

The Duke of York’s daughters looked elegant in a long-sleeved black dress, hat and veil as she drove the car with husbands Jack Brooksbank and Edo Mapelli Mozzi.

Solemn members of the Royal Family gather today as they prepare to accompany the Queen on her harrowing final journey from Buckingham Palace to Westminster Hall, where she will lie in state under the ancient hammer-beam roof.

Princess Eugenie has left Clarence House for the Queen's procession to Westminster Hall

Princess Eugenie has left Clarence House for the Queen’s procession to Westminster Hall

The Duke of York's daughter looked elegant in a long-sleeved black dress, hat and veil as she drove in the car with her husband Jack Brooksbank (pictured in the back seat)

The Duke of York's daughter looked elegant in a long-sleeved black dress, hat and veil as she drove in the car with her husband Jack Brooksbank (pictured in the back seat)

The Duke of York’s daughter looked elegant in a long-sleeved black dress, hat and veil as she drove in the car with her husband Jack Brooksbank (pictured in the back seat)

Princess Eugenie was seen waving to fans as she left Clarence House with her husband Edoardo Mapelli Mozzi, who is already two years old.

Princess Eugenie was seen waving to fans as she left Clarence House with her husband Edoardo Mapelli Mozzi, who is already two years old.

Princess Eugenie was seen waving to fans as she left Clarence House with her husband Edoardo Mapelli Mozzi, who is already two years old.

Not only is the occasion heavily historically significant, but Prince William and Prince Harry are also expected to put aside their feud to support their father by marching behind the coffin with him.

Hundreds of thousands of benefactors are expected to follow the route as they do so.

The Duke of York, the Princess Royal and the Earl of Wessex will also be part of the procession.

Anne’s son Peter Phillips and her husband Vice Admiral Sir Tim Laurence will also walk behind the procession, as will the Duke of Gloucester and the Earl of Snowdon.

The Queen Consort, the Princess of Wales, the Countess of Wessex and the Duchess of Sussex will travel by car. The procession will leave the palace at 2:22 p.m. and is expected to arrive at Westminster Hall at 3 p.m.

Her Majesty spent her last night in Buckingham Palace’s Bow Room before being transported in a coach to Westminster Hall – the ancient heart of Parliament – where she will remain for four days until her funeral on Monday.

Edo, Beatrice's husband, looked earnestly into the car as he left Clarence House this afternoon for the Queen's funeral procession this afternoon

Edo, Beatrice's husband, looked earnestly into the car as he left Clarence House this afternoon for the Queen's funeral procession this afternoon

Edo, Beatrice’s husband, looked earnestly into the car as he left Clarence House this afternoon for the Queen’s funeral procession this afternoon

King Charles III is being driven by police escort to Buckingham Palace in London this morning

King Charles III is being driven by police escort to Buckingham Palace in London this morning

King Charles III is being driven by police escort to Buckingham Palace in London this morning

King Charles III leaves Clarence House in London today for the ceremonial procession of Queen Elizabeth II's coffin

King Charles III leaves Clarence House in London today for the ceremonial procession of Queen Elizabeth II's coffin

King Charles III leaves Clarence House in London today for the ceremonial procession of Queen Elizabeth II’s coffin

More than 1 million people are expected to queue for up to 35 hours in central London to walk past her coffin – but experts think only 400,000 people will get in, meaning 600,000 people will be disappointed.

The Queen arrived at Buckingham Palace last night to tears and cheers from the crowd who stood in the pouring rain to welcome her home after her death in Balmoral last Thursday. The route from RAF Northolt to the palace was packed. There was a wave of lights as many raised their cell phones in the air to film the hearse as it passed.

As the hearse passed through the gates, Charles could be seen bowing his head with Harry and Meghan standing solemnly behind the monarch.

Exactly this afternoon at 2:22 p.m., the Queen’s casket is placed on a carriage and leads a procession through a packed Mall, past Whitehall and then to Parliament Square before entering the Palace of Westminster, followed by her son, the new King, and her children and grandchildren.

King Charles III leaves Clarence House in London today for the ceremonial procession of Queen Elizabeth II's coffin

King Charles III leaves Clarence House in London today for the ceremonial procession of Queen Elizabeth II's coffin

King Charles III leaves Clarence House in London today for the ceremonial procession of Queen Elizabeth II’s coffin

King Charles III waves to the crowd as he arrives at Buckingham Palace in London this morning

King Charles III waves to the crowd as he arrives at Buckingham Palace in London this morning

King Charles III waves to the crowd as he arrives at Buckingham Palace in London this morning

In the nearly 1,000-year-old Westminster Hall, her father, King George VI, would be laid in state in 1952 and where the public could pass the coffin of her mother, the Queen Mother, in 2002. Her Majesty’s closed casket will sit on a catafalque – a raised platform, covered with the Royal Standard with the orb and scepter placed on top.

Charles, William and Harry – along with the Duke of York, the Princess Royal and the Earl of Wessex – will follow the coffin on foot as it makes its 38-minute journey for thousands of mourners along the streets of central London.

For William and Harry, it will bring back painful memories of the time they, aged 15 and 12, walked behind their mother Princess Diana’s coffin in 1997.

Anne’s son Peter Phillips and her husband Vice Admiral Sir Tim Laurence will also walk in the procession, as will the Duke of Gloucester and the Earl of Snowdon.

The Queen Consort, the Princess of Wales, the Countess of Wessex and the Duchess of Sussex will travel by car.

The procession will depart Buckingham Palace at 2:22 p.m., carried by a carriage from the King’s Troop Royal Horse Artillery. The route takes the coffin through the Queen’s Gardens, The Mall, Horse Guards Parade and Horse Guards Arch, Whitehall, Parliament Street, Parliament Square and New Palace Yard.