Prince William arrived at Buckingham Palace to participate in the dual beacon lighting ceremony where he will support the Queen, who will partake from Windsor Castle.
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The Principal Beacon for the Platinum Jubilee takes the form of a lighting installation involving The Queen's Green Canopy Tree of Trees sculpture, and will be accompanied by projections of archive photographs onto the front of Buckingham Palace.
VIDEO: The Queen arrives for the dual-beacon lighting ceremony
The grand structure will be lit up with 3500 festoon lights when Her Majesty symbolically triggers the ceremony from Windsor.
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The event started off with Prince William's arrival and chat with the designers of the illuminating structure, heralding one end of the ceremony 22 miles away.
The Duke of Cambridge arrived in London
The monarch was then greeted by a fanfare of trumpeters and presented with the Commonwealth of Nations Globe, a blue globe that sat on a purple cushion inside a crown, as she walked onto the grounds.
While she was escorted out to the Quadrangle close to her private apartments, she then soldiered on by herself with the help of her walking stick and wore a jade green coat with a silk dress.
The Queen was greeted by the Commonwealth of Nations Globe
The Queen then pressed on the globe, setting off more trumpets as the lights flashed across the gardens of Windsor and raced the entire distance to the Tree of Trees, lighting it up from top to bottom.
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Pressing on the Globe triggered the lights
The Duke looked on, getting emotional the entire time as he saw the symbol of his grandmother's reign lit up in front of him.
The 69-ft Tree of Trees was lit up in front of the royal
After the lighting, William watched the London Community Gospel Choir and singer Gregory Porter perform A Life Lived with Grace in honor of the Queen.
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William interacted with the performers at the ceremony
3500 beacons will be lit across the span of the UK, Channel Islands, Isle of Man, and Overseas Territories, symbolizing her reign.
The celebration ended with projections of the Queen over the years on the palace
While the ceremony was short-lived, it ended with Prince William chatting with Gregory and other students that had been brought there, and luminescent projections of photographs of the monarch on the palace walls.
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