One of the Duke of Edinburgh’s most enduring achievements is his worldwide award programme for young people.
Since it was set up in 1956, the scheme "helped countless young people on their sometimes difficult path to adulthood", according to Prince Philip.
"It’s what I like to describe as a do-it-yourself growing-up kit," he once said.
Those involved in the management of the scheme – often shortened to DofE – paid their respects to the Duke after his death was confirmed by Buckingham Palace.
Ruth Marvel, the scheme’s CEO, said: "The Duke’s timeless vision for young people has never been more relevant or needed.
"The DofE has played a crucial role in supporting young people to survive and thrive despite the unprecedented challenges of the pandemic, and we will continue to build on his legacy.
"The Duke was a lifelong advocate for young people, believing in each individual’s potential.
"We’re honoured to continue HRH’s work, to ensure that all young people – especially those from marginalised groups – can benefit from the better educational outcomes, employment prospects, community ties and better mental health that are associated with doing DofE."
Stephanie Price, director for the DofE in Wales, added: "He was a remarkable man who achieved so much in his life, inspiring many young people.
"It was through his sheer determination, drive and vision that The Duke of Edinburgh’s Award became the success it is today.
"Our charity has transformed the lives of millions of young people from Wales, the rest of the UK and around the world, and remains as relevant to young people’s lives today as it ever was."
The Duke launched the award programme at the instigation of Kurt Hahn, the educational pioneer and founding headmaster of Gordonstoun School, where Philip was a pupil.
The scheme is a programme of activities for young people between 14 and 25.
It is designed to encourage personal discovery, self-reliance, commitment, responsibility and service to the community. There are three separate attainment levels: bronze, silver and gold, each with an increasing degree of commitment.
Currently there are more than 140 countries running the scheme, with more than eight million participants since it started.
In the UK alone, more than three million of the awards have been achieved since 1956, and nearly half a million young people take part at any one time.
Within four years of starting in the UK, it spread rapidly throughout the Commonwealth and beyond.
Overseas the programme is known as The Duke of Edinburgh’s International Award.
Speaking in 2010, the Duke, who remained patron of the charity, said: "It has gone from strength to strength, with 195 awards currently being achieved every day and employers in every field of industry recognising the value of the experiences gained and the skills and characteristics developed by the young people that take part.
"Increased support from like-minded individuals and businesses will make it possible for even more people to take part and achieve a bronze, silver or gold award and help build a brighter future for the United Kingdom."
Those who achieved their gold award got to meet the Prince Philip, who would hand out the awards about 10 times a year at St James’s Palace, the Palace of Hollyroodhouse in Edinburgh or Hillsborough Castle in Northern Ireland.
He celebrated his 500th gold award presentation in 2013.
Prince Edward, an award trustee who took over the award ceremonies from his father, said Philip "was very much the architect of not just the spread of the Duke of Edinburgh’s Award in the UK, but also how it then spread to over 126 countries around the world".
But the Duke was not always keen on the adulation the scheme brought him.
"Her Majesty was standing there and praising the Duke of Edinburgh for the things the award had done," friend and explorer David Hempleman-Adams once recalled.
"And you could tell he was sitting there squirming, wondering when is this going to finish, because he simply didn’t like being told what a great thing he’d given our society."