Thursday marked a significant milestone for the Queen – as she entered the history books as Britain's second-longest serving monarch.
On May 12 the 85-year-old royal beats the record of King George III, who died in 1820, after spending 59 years and 97 days on the throne.
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She is second only to Queen Victoria, who reined for 63 years, seven months and three days.
Queen Elizabeth II celebrated the milestone by indulging in one of her favourite pastimes – her love of horses.
The monarch attended the Royal Windsor Horse Show in Windsor – which takes place in her private grounds at Windsor Castle
A total of 14 of her horses were competing at Britain's biggest outdoor equestrian event, which has been running for over 65 years.
Much to her delight , one of her steeds – named St James – galloped to victory.
Dressed for comfort in a headscarf and a green country jacket, the Queen clapped and cheered with delight when her horse crossed the finishing line.
She was clearly in a very good mood, and was spotted chatting to fellow attendees at the show, including one group of excited teenage girls.
Prince Philip was also on hand – driving a horse-drawn carriage through the grounds.
The royal couple will be in Ireland next week – marking the monarch's first official visit to the Emerald Isle.