The royals were told by a representative: "We know that you unveil a lot of buildings, so we thought we'd do it with a Meta twist." The pair were then presented with a large touch screen so that they could unveil a virtual plaque that commemorated the opening of the headquarters. After they pressed a large button, a white cloth fell away to unveil the realistic-looking plaque that bore both of their names.
WATCH: The Duchess of Cornwall launches volunteering awards
The future King and Queen were then shown around the building which will be home to 5,000 work stations for engineers working on Instagram, as well as the Reality Labs and Workplace.
Camilla was then introduced to four women who volunteer as admins for Facebook group connecting parents and families, before going on to film a video for her own book group, The Reading Room.
She then reunited with her husband, who had been at virtual reality events, and the pair were shown an Instagram filter that will be rolled out for the Queen's platinum jubilee.
The royals unveiled a virtual plaque
However, the royals decided not to be too adventurous when they were given a VR demonstration with neither putting the goggles on, though the Duchess was given some high-tech goggles.
But she was very impressed when shown the StoryTime app, which allowed users to read stories to their relatives who may be far away. "That's brilliant, all those families separated from their grandchildren," she commented.
Their final visit of their outing saw them travel to Meta's London Social Good fair where they toured stalls and heard how the global community is contributing to help those in need in London.
Camilla met some inspiring women
Steve Hatch, Meta’s Vice President for Northern Europe, said: "We're honoured that The Prince of Wales and The Duchess of Cornwall are officially opening our newly built King's Cross offices.
"London is already our largest tech hub outside of the US and our new campus will now be home to thousands of high-skilled engineers.
"Our teams here are building innovative technologies to connect billions of people around the world and help small businesses grow, while also keeping our services safe."
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