King and Queen share a giggle as they struggle to cut cake with sword

The King and Queen saw the funny side when they struggled to cut a cake during a visit to mark the 25th anniversary of the Eden Project.

Charles and Camilla were armed with a sword as they tried to slice a street party-themed Victoria sponge after touring parts of the Cornish ecological centre that opened on March 17, 2001.

As they were shown around the Eden Project, Charles, a former Duke of Cornwall who has visited the site a number of times, said: “I remember when I first came here there was nothing – amazing how it’s developed and grown.”

There was laughter when they first arrived at the landmark Millennium initiative that transformed a clay pit with massive geodesic biomes featuring plant life from around the world to highlight humanity’s reliance on nature.

The King’s state limousine made a wrong turn on the sprawling site and disappeared before doubling back, and Charles quipped as he stepped from the vehicle: “Now you see us, now you don’t.”

During the visit the couple launched The Big Lunch and The Big Help Out, a national celebration of community taking place on June 5-8, and met volunteers and local community and charity groups from across the county enjoying lunch.

A cake showing a street scene of tiny characters enjoying lunch at tables or volunteering in front of a row of houses marked the June event, and Colonel Sir Edward Bolitho, Lord Lieutenant of Cornwall, handed his sword to the couple.

They giggled and they strained to cut through the row of houses, perhaps as they used the end of the sword and so had to use more force.

Sir Tim Smit, co-founder of the Eden Project, said later of the attraction’s history: “Once we started talking to people, I never doubted we’d build it. I never doubted either that it would be successful, not for any reason of arrogance… if you love something and you’re not a freak, there will be millions of people who feel the same way.

“The world has changed since we built Eden. Everybody now knows about climate change. Everybody knows about the impact of all the bad things on the world.

“But at the same time, we’ve got a brilliant generation of young people all over the world coming through who deserve us oldsters to grow up and stop being depressed about it and to get excited that the future still remains us.

“That’s why I’m excited that we’ve done 25 years, and now we’re going to year one of the next 25.”

Charles also tried rolling large wooden marbles from a storm-felled ash tree from the Duchy of Cornwall Estate down a wooden gully – a 25th anniversary Eden Project scheme raising funds for tree planting in Cornwall – and they met the expert teams behind the attractions gardens.

Later, during a visit to the Market House in St Austell town centre, the King had a go at pulling a pint of the alcohol-free Proper Job 0.5% ale.

As he put the glass up to the tap, he asked: “Is this one of your new ones?”

He was told it was the alcohol-free version of the popular Cornish beer.

Shortly before holding up his effort to the cameras and taking a sip, Charles was reunited with Camilla after they separately met different groups of people.

Camilla told her husband: “We’ve come from the other direction. I was told I must catch up with you.”

After leaving the Eden Project, the royal couple had travelled to St Austell and met local community groups in the Holy Trinity Church.

While Charles met teenagers and adults from the Young People Cornwall organisation and faith leaders, Camilla chatted with school children, staff and volunteers from the town’s library.

Camilla watched as reception age children from Mount Charles Primary School in St Austell sang Twinkle, Twinkle, Little Star to her.

The royal couple then walked a short distance to the Grade II-listed Market House to hear about regeneration plans for the building and local area.

Afterwards, they went outside to meet some of the hundreds of well-wishers who had lined Market Hill to catch a glimpse of the couple.