The Queen has travelled to Scotland for Holyrood Week where she has been joined by members of her family including Prince Charles, Princess Anne, and the Earl and Countess of Wessex.
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Buckingham Palace previously said Her Majesty, who experiences ongoing mobility issues, would not take a decision on whether to travel to Edinburgh until nearer the time. But on Monday, she took part in the Ceremony of the Keys with the Earl and Countess.
WATCH: The Queen travels to Scotland for rare public engagement
The ancient ceremony took place on the forecourt of Holyroodhouse, the Queen's official residence in Scotland, as part of Holyrood Week – also known as Royal Week.
As part of the tradition, the monarch is symbolically handed the keys of the city by the Lord Provost and tradition dictates she then returns them, entrusting their safekeeping to Edinburgh's elected officials.
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She appeared on good form as she beamed with delight and watched the ceremony, using her walking stick as an aid.
The Queen was pictured using her walking stick at the event
This isn't the only public engagement the Queen is undertaking in Scotland for Holyrood Week. On Tuesday, she is confirmed to attend an armed forces ceremony in the gardens of the Palace of Holyroodhouse.
The event will see members of the armed forces parade as part of the presentation of the key for Edinburgh Castle. It will be an opportunity to celebrate the Queen's Platinum Jubilee and pay tribute to her role as head of the UK armed forces.
The Governor of Edinburgh Castle, assisted by three service cadets, is due to address the Queen with: "We, the serving members of Your Majesty's armed forces, bound by our oath to you, your heirs and successors, offer for your gracious acceptance the key to Your Majesty's Royal Castle of Edinburgh."
The Queen will respond: "I return this key to the safekeeping of My Governor of Edinburgh Castle, in gratitude for the symbolic act of loyalty of our armed forces, confident of your faithful allegiance to your oath."
Sophie Wessex beamed with delight at the Queen during the engagement
Other royals will also take part in engagements between Monday and Friday. On Tuesday, Princess Anne will conduct an investiture on behalf of the Queen at Holyroodhouse.
On Wednesday, the garden party at Holyroodhouse will take place hosted by Charles, Anne, Edward and Sophie. Guests invited are those who have made positive contributions to communities across Scotland.
She was symbolically and physically handed the keys to Edinburgh
On Friday, Charles will attend a Queen's Body Guard for Scotland Reddendo Parade in the gardens of the palace. He and Anne will also attend the Thistle Service at St Giles' Cathedral.
Edward will also host a celebration in the gardens at Holyroodhouse for Duke of Edinburgh Gold Award holders from across Scotland on Friday.
She was joined by Prince Edward and his wife Sophie
Scotland holds a special place in the Queen's heart. The monarch, 96, usually travels to her private estate, Balmoral, in July and stays there for an extended summer break until October. She was most recently in Scotland at the end of May where she spent a few days resting and relaxing at Balmoral ahead of her busy Platinum Jubilee bank holiday weekend.
Her granddaughter Princess Eugenie has previously revealed that the Queen is "happiest" at her rural Scottish estate. "I think Granny is the most happy there," Eugenie said in documentary, Our Queen At Ninety. "I think she really, really loves the Highlands. Walks, picnics, dogs – a lot of dogs, there's always dogs – and people coming in and out all the time."
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