Queen Elizabeth II's death certificate confirms Britain's longest reigning monarch died of old age.
The certificate, published by National Records of Scotland Thursday, records that Elizabeth died Sept. 8 at 3.10 p.m. The document was signed by the queen’s daughter, Princess Anne.
The confirmation comes days after the royal period of mourning ended which included flags being flown at half mast and the royal residences and private estates being closed.
The queen died at Balmoral Castle in Scotland. She was 96. The palace issued a black-bordered statement about 6.30 p.m. local time that day, saying she "died peacefully." Her 73-year-old son, and heir to the throne, King Charles III, immediately became king upon her death.
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Queen Elizabeth remained active for a long time despite her old age but in recent months her health declined. She struggled with mobility issues, causing her to skip events and postpone meetings at the suggestion of her doctors.
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The news of her death came a day after the queen postponed a meeting of senior governmental advisers known as the Privy Council. A few days prior, she decided to skip the Braemar Gathering, a popular Highland Games event she loves and attends every year.
Before the queen's funeral Sept. 19, tens of thousands of people shuffled through Westminster Hall over four days to see the queen’s lying in state.
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Royal fans continued to pay respects to Queen Elizabeth Thursday, as hundreds lined up outside Windsor Castle where the late monarch was buried. It opened to the public Thursday for the first time since her death.
Her tomb is marked by a slab of hand-carved Belgian black marble inside the King George VI Memorial Chapel, part of St. George’s Chapel at Windsor Castle. The queen’s name is inscribed on the ledger stone in brass letter inlays, alongside the names of her husband, mother and father.
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To visit the chapel, royal fans have to buy a ticket to Windsor Castle.
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The memorial chapel sits within the walls of St. George’s Chapel, where many members of the royal family are buried. It has also been the venue for several royal weddings, including the marriage of Prince Harry to the former Meghan Markle in 2018.
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Contributing: The Associated Press; Morgan Hines, Kim Hjelmgaard, Maria Puente, Laura Trujillo, USA TODAY
This article originally appeared on USA TODAY: Queen Elizabeth cause of death: Monarch died of old age