WATCH: The royal family's most iconic Ascot moments through the years
Shibumi is a small boutique based in Horsley, Gloucestershire, which offers bespoke services and prides itself on offering inclusive sizes.
Princess Anne has been loyal to the ethical designs for years and showed her love of supporting independent brands in her choice of Ascot attire.
The 70-year-old royal also channelled her mother The Queen with an elegant two-string pearl necklace and delicate drop earrings.
The royal aptly accessoried with a golden horse brooch
No royal outfit would be complete without a statement brooch, and the Princess Royal chose the perfect gold horse accessory for the occasion. Anne has not only had a successful equestrian career, but was the first member of the royal family to compete in the Olympics, riding the Queen's horse, Goodwill, in Eventing at the 1976 Games in Montreal.
Anne, who is renowned for her frugal fashion sense, appears to have owned the brooch since the 1980s and has regularly worn the accessory for the races, including Cheltenham Festival and Royal Ascot.
Completing her look with a fascinator, Anne fashioned a dramatic blue hat with a decorative peacock-esque feature, which she wore on top of her classic chignon hairstyle, looking exquisite for the first day of the races.
Princess Anne opted for flats over heels for the first day of the races
The Princess Royal's sister-in-law the Duchess of Cornwall also opted for blue, wearing a chic striped pastel dress, matching face mask and elegant blue fascinator.
Ascot is known for its strict dress code – no outfits above the knee, strapless dresses are a big fashion faux pas and hats or fascinators are a must. No one does Ascot style better than the royal family, however, who are used to adhering to similar fashion on a daily basis.
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