The Prince of Wales has recalled how he tried surfing “rather unsuccessfully” 40 years ago.
Charles was speaking in Nansledan outside Newquay in Cornwall, where he was announced as patron of Surfers Against Sewage.
The charity was founded in 1990 to protect oceans, waves, beaches and wildlife.
Dark oak from the prince’s Highgrove Estate was used to create the surfboard.
“I am touched and grateful to be asked to be patron of this amazing organisation,” Charles said.
“I do admire enormously all that you are trying to do in different parts of the country and indeed, probably around the world.
“How you mobilise quite so many people is astonishing. I can only congratulate all of you on the efforts you make.”
He added: “Having tried to do a bit of surfing myself 40-something years ago, rather unsuccessfully, I only wish I was still able to do it and try out this board.”
The reception was held at Nansledan School, or Skol Nansledan, which opened in September.
Charles toured the school and met pupils taking part in a workshop with Surfers Against Sewage.
When they replied that they had, Charles asked: “Did you get a pudding as well?”
In a reception class, the prince was approached by five-year-old Whitney, who handed him a picture she had drawn.
“Thank you very much,” Charles told her.
“Who is this? Me? You are very lucky I’m not going to draw one of you.”
The picture featured a sketch of the prince in yellow and blue pencil.
Whitney had then written: “To Prins Charess. My name is Whitney. I love you. I have sor you before xx”.
He was shown the production process of their slippers from raw sheepskin to ready for sale.
Before leaving Charles, patron of Campaign for Wool, was gifted a pair of their slippers.
When he was told there was a pair for wife the Duchess of Cornwall in the bag, he replied: “Thank goodness for that”.
Celtic & Co was started by Nick and Kath Whitworth as a small boot-making business in 1990.
It now ships to customers in more than 60 countries, employs 52 permanent staff and had an £8.9 million annual turnover last year.
Products are sustainably made from material such as wool, sheepskin and linen.