The Monarch, 96, was driven the short distance from Windsor Castle to the Copper Horse Arena at the show in Home Park on Friday, May 13.
It marked the first time the Queen has been seen in public since the Duke of Edinburgh’s memorial service in March.
The Monarch was reportedly due to watch her horse Balmoral Leia compete in the Horse & Hound Mountains and Moorlands in Hand event for Fell ponies at 10.30 am.
The Queen was spotted being driven to the arena before the event began.
Her Majesty was seen rolling down the window and smiling as she sat in the passenger seat.
The Royal Windsor Horse Show is thought to be one of the Queen’s favourite events of the year.
She is said to have attended every year since the competition was founded in 1943 as a wartime fundraising event.
The live show was cancelled in 2020 due to the COVID-19 pandemic and was instead conducted online.
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