She will later be laid to rest in a private family service beneath St George's Chapel with her husband of 73 years; her sister, Margaret; and her parents. The queen's casket entered Westminster Abbey around 11 a.m. local time, exiting around noon, after the funeral proceedings.
Millions of people all over London flocked to the streets to mark the occasion.
Here are the most important moments you need to know from the monumental day:
Solemn, at times emotional royal family photographed: Princess Charlotte, Duchess Meghan crying, King Charles III teary-eyed
All members of the royal family expectedly appeared solemn over the course of the day, especially the queen's four children: King Charles III, Princess Anne, Prince Andrew and Prince Edward.
The king's eldest son and his family – Prince William; Catherine, Princess of Wales; Prince George and Princess Charlotte – arrived as a united front to Westminster Abbey with their heads bowed. Their youngest child, Prince Louis, 4, was not in attendance.
Emotions ran high after the funeral, too. Princess Charlotte could later be seen crying beside her mother, Kate. The children's presence reminds royal watchers the next generation of the monarchy is watching, waiting and ready to perform their royal duties.
In a committal service that followed the funeral at Windsor Castle, the crown, scepter and orb were removed from the top of the queen's casket. The items were placed on an altar at St George’s Chapel, and marked the final separation of the late queen from her crown. King Charles III stood by during the moments of farewell, and appeared teary-eyed.
The queen’s casket was lowered into the vault, a solemn scene shown in TV coverage. Later, the queen will rest with her husband, Prince Philip, during a private service for the family.
King Charles III leaves note atop queen's funeral wreath: 'In loving and devoted memory'
The queen's casket was adorned with a funeral wreath that included flowers and foliage cut from the gardens of Buckingham Palace, Clarence House and the king’s private home Highgrove House, per the palace's notes on the funeral.
The foliage was chosen for its symbolism: Rosemary for remembrance. Myrtle for the ancient symbol of a happy marriage, and cut from a plant grown from a sprig of myrtle in the queen’s 1947 wedding bouquet. English oak symbolizes the strength of love.
Also included were scented pelargoniums, garden roses, autumnal hydrangea, sedum, dahlias and scabious, in shades of gold, pink and deep burgundy, with touches of white to reflect the Royal Standard.
Atop the wreath? A note from Charles, honoring his mother: "In loving and devoted memory. Charles R," it read.
"Charles R" is the monarch’s official signature, with R being Latin for "Rex," or king. (Elizabeth’s signature was Elizabeth R, for "Regina," Latin for queen.)
The sight of that note immediately evoked memories of the note that sat on Princess Diana’s casket during her funeral procession to Westminster Abbey in 1997. It was from her sons and signed "Mummy."
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Kate, Charlotte, Meghan wore jewelry that honored the queen
Members of the royal family remembered their beloved matriarch in traditional black funeral attire, but added meaningful jewelry.
Kate wore two pieces of jewelry that once belonged to her grandmother-in-law. She wore Bahrain pearl drop earrings and a four-strand pearl choker necklace, both from the queen's collection, People reported.
Her daughter, Charlotte, wore a dainty brooch on her coat in the shape of a horseshoe, a tribute to her great-grandmother, who had a lifelong passion for horses.
Meghan also wore delicate pearl earrings from the queen.
The choir sang a song from the queen's wedding
The choir of St George's Chapel sang as a procession – including King Charles III, William, Kate, Prince Harry, Meghan, George, Charlotte, Anne, Andrew and Edward – followed the queen's casket into the abbey.
The choir of the Westminster Abbey sang "The Sentences," written by William Croft, whose "Sentences" have been used since the mid-1500s and at every state funeral since the early 18th century.
The group later joined with the choir of the Chapel Royal for a rendition of "Like As the Heart." The funeral's attendees sang "The Day Thou Gavest, Lord, Is Ended."
The choir also sang "The Lord’s My Shepherd," which was heard at the wedding of the queen and Philip. The choir sang "God Save the King," featuring different lyrics from what many have known for decades as "God Save the Queen," as the funeral concluded.
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Queen Elizabeth's corgis, monarch's fell pony made it
It wouldn't be a day honoring the queen without the presence of her beloved corgis, Muick and Sandy. The pair were spotted (leashed, of course) ahead of the committal service. The two dogs are expected to live with Andrew and Sarah, the Duchess of York.
Also in attendance? Emma, the monarch's fell pony, stood by as the ceremonial procession of the coffin arrived at Windsor Castle for the committal service. Thousands upon thousands of flowers – cut, not planted – dotted the route.
Millions of Londoners mourn the queen: 'Mixed emotions'
The Hyde Park viewing area was filled with hundreds of people, mainly in black and many of them holding British flags. Some were having full picnics, others dozing until the ceremony started.
Members of the public lined the road outside Hyde Park, to the background of music from the marching band and periodic gun salutes. Elyas Hussein, 45, traveled 125 miles from Birmingham, England, to watch the funeral on the big screen in Hyde Park.
He said he had "mixed emotions" watching the ceremony.
"She represented the Commonwealth," Hussein said of the queen. He said his father served in the British Army’s Pakistan regiment, and both his uncles also served in the British Army.
"I think King Charles will emulate his mother," he said. "He’s done a lot for young people with the Prince’s Trust," referring to Charles’ youth charity that helps young people get jobs and education.
Lucy Hartnell, 26, of Hertfordshire, organized a picnic at Hyde Park of what they assumed were "queen favorites": strawberries, cucumber finger sandwiches, Prosecco, cupcakes and chips. They took the tube into London and were "shocked" how easy it was for them to get to Hyde Park to view the funeral. They expected much more of a "struggle."
They said they were more there to be immersed in the event and aren’t very pro-royal or anti-royal, which has been a large debate among young people.
Contributing: Maria Puente, Nicole Fallert, Naledi Ushe, Hannah Yasharoff, Amy Haneline, Jane Onyanga-Omara, Kim Hjelmgaard and Morgan Hines, USA TODAY
This article originally appeared on USA TODAY: Queen Elizabeth funeral moments: Wreath, fashion, Charlotte crying