Prince Charles and Camilla kept tight-lipped about Saturday's royal wedding as they spent a day meeting innovators in fashion, design and technology across London.
At YouTube's King's Cross outpost, the couple tried on virtual reality headsets and scanned the room in a circle. "You start feeling very dizzy," said Charles, laughing.
The pair also met YouTube stars Joe Sugg and Louise Pentland.
Mr Sugg, 26, said: "I grew up near Camilla, near one of her houses, and my job was thatching roofs, and she used to walk past with her dogs and say hello, and she remembered that, which was really nice."
The couple tried their hand at thatching a roof, which had been set up in a studio.
"He's got a great sense of humour. If he is looking for a thatching job, I'd hire him," said Mr Sugg of the prince.
The YouTube star has more than eight million subscribers to his ThatcherJoe channel, where he produces videos ranging from prank calls to impressions.
Charles also met young people who had their lives turned around by the Prince's Trust, and took part in a debate on knife crime and social media.
Omar Sharif, 26, was stabbed when he was part of a gang aged 17. Fearing for his safety he moved to Coventry, but with few qualifications struggled to find a job.
"I saw an advert for the Prince's Trust and I had heard of it, but didn't quite know what it was. I was 19, and married, so I had to support a family and the programme really changed my outlook.
"I was depressed when I moved from London, and had gained weight, so while on a fat-loss programme they gave me the idea to set up a boot camp and run it. I had 100 people a week, so they helped me again with a start-up programme and that allowed me to start my business."
Mr Sharif now runs his own personal training company in Coventry, working in some of the cities biggest gyms.
"The Prince's Trust gave me something to be proud of," he said.
During the discussion, the Prince said: "I was so incredibly fed up of meeting these poor people who'd had their sons or daughters killed or stabbed. They call them Families United, and I couldn't bear it, I think there must be a way to try and help and this, I hope, is one way of doing it."
Visiting Yoox Net-a-Porter's tech hub in White City, Charles and Camilla met schoolgirls who had been learning to code.
The Duchess of Cornwall, taking a keen interest, said: "I think it's brilliant, very clever."
One of the girls, Sophie Belonogova from Holland Park school, said the experience was "amazing."
The couple were shown a new app from The Outnet - an online shopping site launching pages in Arabic next week. A jovial Prince Charles asked around the room: "Are you responsible for the Arabic? I hope you have got it right."
The last stop on the trip was Soho House's new outpost in White City, where the Prince vigorously cut through the red ribbon and declared the members' club open for business.
Inside, members of the British Fashion Council were showcasing their works and greeted Charles.
British Vogue editor-in-chief Edward Enninful was meeting the Prince of Wales for the first time. He said: "I love what he does for fashion, the new generation. I'm a huge fan. It's a real honour."
When asked what Charles should wear to Saturday's royal wedding, Enninful laughed, saying: "He's pretty used to royal weddings, he doesn't need any advice from me. I think he looks great. He always does."