Prince Charles spoke at the Social Action Awards
Speaking at an award ceremony recognising the achievements of members of uniformed youth organisations such as the Scouts and St John Ambulance, he said his time as a young volunteer was "very good" for him.
The Social Action Awards were organised by the umbrella organisation Youth United which, through its charitable arm, funds the creation of new volunteering places for youngsters in deprived and disadvantaged areas of the country.
The Prince, who is Youth United's founder and patron, told guests at the Buckingham Palace ceremony: "Interestingly, I was a cadet myself years ago, dread to think it was in the 1960s I suppose, and I did rather enjoy my time as a cadet, very good for me it was I think."
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Prince Charles spoke about his time at Gordonstoun school
We actually had to do real-life coastguard work
Speaking about his time at Gordonstoun school in Morayshire, Charles added: "And also, I then became a coastguard at the school I was at in Scotland.
"We actually had to do real-life coastguard work."
He made his audience laugh when he said: "We had a coastguard lookout on the coast on the cliffs, and most of the time we spent hoping that some enormous aircraft carrier would run aground so that we could rescue the entire crew with what was then a very complicated set of breeches buoys."
Prince Charles in pictures
Fri, December 16, 2016
Prince Charles as he tours the world for his royal visits.
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Prince of Wales in Clarence House, London as he records a special message for BBC Radio 4's Just a Minute as it enters its 50th anniversary year which will be aired on Christmas Day
Prince Charles made his audience laugh
Youth United is made up of 11 member organisations from the RAF Air Cadets and the Jewish Lads' and Girls' Brigade to the Scout Association and Girlguiding.
The Social Action Awards highlight the achievements of new branches of Youth United member organisations.
The winners ranged from volunteer police cadets from Wisbech fire station and Meadowgate in Cambridgeshire, who cleared litter from a local area, to Newham Cornwell VC Sea Cadets from London, who made up toiletry shoeboxes for the homeless.
Prince Charles had a coastguard lookout on the coast
Kim Pybus, the executive officer of the winning sea cadets organisation, said: "The shoebox project for a homeless shelter was amazing, it was the juniors' pocket money that actually purchased all the items for the shoeboxes – socks, hats, gloves and other essential items a homeless person would need."
Before the presentations were made, Rob Wilson, the minister for civil society, gave a speech and told the guests: "We know that by giving young people an opportunity at an early age, they go on to become leaders of their own social change and help to build strong communities."