She accessorised with simple black shoes and a handbag – and looked delighted as she walked the gardens with a string of pearls around her neck.
The Queen attended the UK’s renowned Chelsea Flower Show ahead of the opening of the event.
She was accompanied for the occasion by Princess Anne, the Duke and Duchess of Gloucester and Princess Alexandra.
The event marked the Queen’s first Royal duty – since the weekend’s spectacular Royal wedding.
Her husband, Prince Philip, was, however, absent as he officially retired from royal duties last year.
For Saturday’s wedding, the Queen wore a vibrant shade – as is her usual custom.
A fanfare played as the Queen made her way into St George’s Chapel and took up her seat.
Meghan’s bridesmaids and pageboys arrived as the Queen made her entrance.
Among them were Prince George and Princess Charlotte, the two eldest children of the Duke and Duchess of Cambridge.
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