The Queen has been the Captain-General of the Royal Artillery Regiment for sixty five years and today she joined them on Salisbury Plain - as they celebrated their three hundredth anniversary celebrations.
Dressed in pale pink, Her Majesty arrived by helicopter to be greeted by the thousands who had turned out for the special visit.
Known as the Gunners, the regiment provides the fire power for the British Army.
The Queen was greeted with a 21 gun salute during a day of celebrations. Rachel Hepworth reports.
This weekend marks a very special public celebration of Her Majesty the Queen Elizabeth's ninetieth birthday.
The events and shows at Windsor include more than 1,500 performers from across the globe, hundreds of horses and more than 25,000 spectators.
ITV Meridian's Sangeeta Bhabra and Simon Parkin presented the live programme from the grounds of Windsor Castle, speaking to many of the people taking part both in front of, and behind the scenes. Join us in a celebration of the 90th birthday of Her Majesty the Queen.
The Queen and her husband, the Duke of Edinburgh, will attend the final night of celebrations on Sunday. There will be live coverage of the star-studded event in a programme hosted by Ant & Dec, on ITV from 8.35pm on the evening of Sunday 15th May..
The Queen's love of horses is well documented and that passion is reflected in the celebrations over the next few nights.
As a young princess she enjoyed riding in Windsor Great Park - something she still does today.
The Queen owns and breeds thoroughbreds. Those close to her say horse racing is when she really relaxes. Penny Silvester has been talking to the Queen's Racing Advisor, John Warren, about why her affection for these animals runs so deep.
On Sunday, The King's Troop will perform in front of the Queen and it's taken months of training to get them ready.
The soldiers on horseback were first formed in 1946 to be a show piece during ceremonies of state. Simon Parkin went to see them rehearsing.
The Queen's 90th birthday celebrations in Windsor this weekend are set to be an event to remember. The offering will feature one and a half thousand performers from across the world, 900 horses, 25,000 spectators and a very special guest of honour.
We've met some of the acts taking part and we've been speaking to those who know the Queen personally.
Last-minute sound checks and rehearsals have been happening today in the main arena, ready for this evening's events. But the day started with the 73rd Royal Windsor Horse Show. Here's Mike Pearse.
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.
The Royal Navy will mark the birthday of Queen Elizabeth II with a 21-gun salute at Fort Blockhouse in Gosport today.
The event is one of many taking place at military establishments across the country. At Portsmouth's Naval base, Royal Navy ships will celebrate with flags displayed along their sides.
Gurkha soldiers in Kent have been scaling the Leas cliff in Folkestone in their battle against litter.
The efforts of the Royal Gurkha Rifles 2nd Battalion is in honour of the Queen's 90th birthday, and is one of a series of clean-ups coordinated by Shepway District Council as part of the national 'Clean for the Queen' campaign.
It is being billed as a huge party for the Queen - a star studded show in the grounds of Windsor Castle, to mark her Majesty's 90th birthday.
Now it has been revealed the event in May, which will be broadcast live on ITV, will be hosted by Britain's most popular TV duo Ant and Dec. As Rachel Hepworth reports, preparations are well under way.
The interviewees are: Simon Brooks-Ward, Director of the Queens's birthday celebrations; the singer Katherine Jenkins; Pau Roach, Windsor & Eton town manager; and Julia White, Windsor Visitor manager.
The Queen's love of horses is well-documented and today she got to meet the next generation of equine vets as she officially opened a new state-of-the-art veterinary school in Guildford.
Her Majesty and the Duke of Edinburgh were also given a tour of the £45 million facility. The University of Surrey is aiming to deliver cutting-edge teaching and research.
The school boasts a large clinical skills facility and what the university says is one of the best veterinary pathology centres in Europe.
Watch Emma Wilkinson's report:
Interviewee: Professor Chris Proudman, Head of Veterinary School, University of Surrey.