There’ll be performances from actors, musicians, bands, dancers and the military and the event has been designed to reflect The Queen’s love of horses, her connections with the Armed Forces and the Commonwealth.
Queen Elizabeth II (centre) has been attending the third day of the Royal Windsor Horse Show, which is held in the grounds of Windsor Castle in Berkshire. The next few days hold major celebrations to mark Her Majesty's 90th birthday.
More on the celebrations marking The Queen at 90.
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A vigil has been held to remember the three victims of the terror attack in Reading.