The Royal Family has had a long association with Ascot. The racecourse in Berkshire was founded by Queen Anne in 1711, and has since received the patronage of a further 11 monarchs.
The Ascot summer race meeting officially became a Royal week in 1911, during the reign of King George V, and The late Queen Elizabeth attended the fixture from 1946, when she was then Princess Elizabeth.
Her Majesty was an owner and breeder of many thoroughbred horses and shared her interest in horses with many members of her family — including her daughter Princess Anne and King Charles.
Her own horses have won races at Royal Ascot a number of times, the first being in 1953.
What happens on the day?
Each day of the week begins with the Royal Procession at 2pm, when the King and accompanying members of the Royal Family arrive along the track in horse-drawn landaus (four-wheeled luxury carriages).
King George IV started the traditional carriage procession at Royal Ascot in 1825.
The first race of the day begins at 2.30pm and the royals spend the rest of the afternoon watching from the Royal Enclosure.
Can you buy tickets for the Royal Enclosure?
Unfortunately not. It was first established in 1807 exclusively for the family, guests and household of King George III, and to this day membership continues to be by invitation-only.
Members can book badges for themselves and their guests, book car parking or sponsor new members.
What do the royals wear?
There is a strict dress code for the Royal Enclosure, although for other enclosures the rules around what to wear has been loosened in recent years to accommodate all visitors — and their budgets.
In the royal enclosure, however, rules remain pretty much in tact: women should wear dresses and skirts of modest length, which fall just above the knee or longer, while dresses and tops should have straps of one inch or greater.
While trouser suits and jumpsuits are welcome in the Royal Enclosure, strapless, off-the-shoulder, halter neck and spaghetti straps are not permitted. Jackets and pashminas may also be worn.
The hat rules are also very precise. Hats are compulsory, otherwise a headpiece which has a solid base of four inches (10cm) or more in diameter is acceptable as an alternative to a hat. Fascinators are not permitted.
Men are required to wear either black or grey morning dress, which must include a waistcoat and tie, a black or grey top hat and black shoes worn with socks.
The King attends with members of the Royal Family throughout the week, who join him in the carriage procession.
The most notable debuts at the racecourse often include those who have married into the Royal Family, who take the opportunity to ensure their Ascot looks are ones to remember.
Princess Diana attended for the first time in 1981, just weeks before her wedding to Prince Charles.
The Princess of Wales made her debut in 2016 wearing a white lace Dolce & Gabbana dress, five years after she married Prince William.
Two years later, the Duchess of Sussex channelled Audrey Hepburn in a white Givenchy shirt dress with a black waist belt in 2018, not long after she had married into the Royal Family.
This year will be Charles's first attendance since taking the throne, and while it might be bittersweet to be back at an event so beloved by his late mother, it marks a new chapter for the House of Windsor under his stewardship.
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