He walked in both as a king–in–waiting and a nervous teenager about to embark on a thrilling new chapter of his life.
But, aside from receiving a reassuring pat on his back from his mother the Princess of Wales, Prince George, 13, was the picture of calm as he arrived for his first day at historic £65,000–a–year Eton College.
Sporting a blazer, tie and chinos, the second in line to the throne strode briskly through the rain and across the world–famous public school's quadrangle – known to pupils as School Yard.
The family had emerged moments earlier from the arch beneath Lupton's Tower, the school's 16th century gatehouse clock tower.
Catherine, dressed in a low–key but elegant green dress, held up a large golf umbrella and hung ever so slightly back as her son stepped forward confidently next to his father, Prince William, to be greeted by headmaster Simon Henderson and college Provost Sir Nicholas Coleridge, who serves as the chairman of the governing body, with firm handshakes.
'George welcome, good luck, enjoy,' Mr Henderson beamed.
While there may have been nerves on both sides, it was smiles all round as the group exchanged pleasantries, although the heavy rain drowned out the sound of their conversation.
The princess, in particular, had the beatific look of all proud mums as they watch their children doing something rather well.
A portrait of Prince George in his uniform as he begins his first day at Eton College this morning
The trio strode through Eton College's historic School Yard quadrangle in the heavy rain
Eventually, Mr Henderson invited them in out of the rain and the all–too brief photocall was over, George disappearing into what his family hope will be the anonymity of school life.
It seems hard to believe that the self–assured young man in front of us was, only a few years ago, being introduced to the world on the steps of the Lindo Wing at St Mary's Hospital, Paddington – or was pictured, tousle–haired, his back pack almost as big as him, on his first day at nursery.
The photocall had been arranged for 11am, half an hour before the rest of his fellow 'F Blockers' – Eton shorthand for first year pupils – arrived.
It is the only time during the next five years George is likely to get any special treatment – and even then the decision was more about protecting the privacy of the other children.
All new pupils arrive in their own clothes before changing into Eton's distinctive uniform, which includes a black tailcoat, waistcoat and white tunic shirt.
Kensington Palace later released three portraits of an assured–looking George taken in situ by one of their favourite photographers, Matt Porteous.
William and Catherine, like all parents, stayed to watch their son add his signature to the same visitors' book his father and uncle, Prince Harry, signed on their own first days at Eton, before helping him settle into his new bedroom. But then it was time to say goodbye.
The prince and princess have made clear how grateful they are for the way the media and public have allowed their three children to grow up and enjoy their education away from the spotlight, and hope this will continue for George as he moves through his senior school years, despite the ever–present threat of mobile phone photography.
Prince William on his way to his first day at Eton School in 1995
Princess Diana and Charles with William and Harry outside Eton on William's first day in 1995
The young prince's arrival at the exclusive public school differed markedly from his father's first day on September 6, 1995.
Then William was photographed arriving at his boarding house in front of 300 members of the world's media.
He was accompanied by his parents Prince Charles and Diana, Princess of Wales, who had by then been separated for three years, along with his now estranged younger brother. Eton was always the frontrunner for William and Catherine when it came to choosing a senior school for their eldest child, but it was by no means a done deal. The couple have been spotted checking out a number of other boarding schools.
What swung it was Eton's proximity to the family's 'forever home' at Windsor, Forest Lodge, the fact that the college has long experience of dealing with the complexities around high–profile pupils and, of course, George's own preference.
He is likely to be joined by a number of friends from Lambrook, the co–educational prep school in Berkshire he has attended with his siblings in recent years. It also helps that William has genuinely fond memories of his own time there: He made close friends who remain part of his inner circle today and adored being able to nip 'back over the bridge' to nearby Windsor Castle to see 'granny'.
William and Catherine hope George's time at Eton will be among the happiest years of his life, allowing him to develop away from the spotlight and develop a tight–knit circle of friends that will support him for many decades to come.
He is said to be a hugely outdoorsy, sporty boy, who has shown a talent for triathlon and sailing – and is obsessed by flying – and is likely to 'fit right in'.
The college was founded in 1440 to provide free education for 70 poor boys before they progressed to King's College, Cambridge.