Armistice Day was, as it usually is, a cold day. A cold day for a younger generation of military personnel and observers; and an even colder day for the older generation of Second World War veterans, many of whom were in their 80s.
Which is hardly surprising; he has been in hospital a number of times this year and had abdominal surgery in June. He looked every single one of his 92 years; frail, thin, hollow-cheeked, and almost cadaverous.
Many people watching the ceremonies, particularly those watching from the comfort of home, must have wondered why this old man needed to be in Belgium, needed to be braving the elements. Hasn't he enough sons and grandsons to lift the weight from his drooping shoulders?
Maybe so, yet for the Duke of Edinburgh it has never been about asking others to stand in for him when he's having an off-day. For him it has always been about duty.
The duty he owes to his wife as Queen, the duty he owes to his adopted country, the duty he owes to a monarchy which has known some rocky moments down the years, and the duty he owes to himself as someone who was never going to be a mere consort following a few steps behind Her Majesty.
It's very easy – too easy at times, given his penchant for off-the-cuff comments and one-liners – to try and dismiss him as some sort of relic of a bygone age, someone who doesn't quite fit into the 'modern' concept of what a monarchy is supposed to be.
Yet for the 'modern' media it's always been easier to go for the latest politically incorrect gaffe than to spend too much time concentrating on the fact that everything he does is in the name of duty.
Who could have done anything about it, for example, had he opted for an easy, pampered life and spent his time amusing himself? He's the Queen's husband, after all, so while she's about he's going to be somewhere close. But over the decades he has chosen – and it has always been his choice – to be particularly close.
That sense of duty, that constant, never-ending sense of duty, owes much to his early life. He was born on June 10, 1921 on the Greek island of Corfu, the only son (there were four elder sisters) of Prince Andrew of Greece and Denmark and Princess Alice of Battenberg.
A war was raging between Greece and Turkey at the time and his father was the commander of an army division.
By the autumn of 1922, the Turks had made large gains and Philip's uncle, King Constantine, was forced to abdicate. A few months later, Prince Andrew and his family were banished for life from Greece and a British naval vessel evacuated them (18-month-old Philip was carried to safety in a cot made from a fruit box) to a family home in Paris. His early education involved a number of locations: an American school in Paris (where he was described as "a rugged, boisterous, but always remarkably polite boy"), Cheam School in Berkshire (where he lived with his maternal grandmother at Kensington Palace), Schule Schloss Salem, in Germany (run by his brother-in-law), and Gordonstoun, in Scotland (where he moved after the rise of Nazism).
During that period, his mother was placed in an asylum, having been diagnosed with schizophrenia, and his four sisters all married German princes and moved to Germany. His father, meanwhile, sought sanctuary in a flat in Monte Carlo.
In 1939, just before the outbreak of war, Philip joined the Royal Navy and a year later graduated from the Royal Naval College, Dartmouth, as top cadet. He continued to serve with the British forces while two of his brothers-in-law fought for the Germans.
He had what used to be known as a 'good war' – serving on a number of vessels, earning promotion and being 'mentioned in dispatches'. He was popular and respected across all ranks.
Philip first met Princess Elizabeth in 1939 (his third cousin) when she was 13 and he was 18. Within a matter of weeks, they were exchanging letters and after a few months had clearly fallen in love.
But it wasn't until the summer of 1946 that he asked King George VI for permission to marry her, a permission that was granted on the condition that the engagement wouldn't be announced until she turned 21 the following year. In the meantime Philip renounced all claims to the Greek and Danish thrones, converted to Anglicanism (from Greek Orthodox), formally took the name Mountbatten, and became a naturalised British citizen.
He wasn't just marrying Princess Elizabeth, he was marrying the heir to the throne, her history, her people, her values and her responsibilities. He was committing himself to a lifetime of being a very public figure, yet a public figure who would forever remain in the shadow of another much more important public figure. This was always going to be difficult for a proud, ambitious man.
He had spent most of his life so far rootless, never quite a royal, never quite a commoner; never quite Greek and never quite British. If anything happened to Elizabeth, he would return to that rootlessness, because he would never be king in his own right.
The couple were married on November 20, 1947 (in the morning, a few hours before the ceremony, he was made the Duke of Edinburgh), yet such were the post-war sensitivities that his three remaining sisters – still living in Germany – were not invited to the wedding.
The break with his past was complete. He had put his commitment to his new wife and his adopted country before everything else and that sense of duty to her and the country have been the bedrock of his life for the 66 years.
He hasn't always been popular with the people and the media. Some of his public and supposedly private comments and observations have been regarded as racist, wounding, insensitive and provocative.
The historian David Starkey described him as 'HRH Victor Meldrew', while Philip himself has admitted that some of his off-the-cuff remarks have "added to the impression that I am a cantankerous old sod. Well, I'm not."
Some commentators believe that he was on the 'wrong side' of the Charles and Diana fallout, while others believe that he put the interests of the monarchy before their personal interests.
More so than any other member of the royal family – given the fact that his own family was deposed in Greece – he understands the challenges to any monarchy. Indeed, back in 1969, in response to a question about the growth of republicanism, he said: "It is a complete misconception to imagine that the monarchy exists in the interests of the monarch. It doesn't. It exists in the interests of the people. If at any time any nation decides that the system is unacceptable, then it is up to them to change it."
This country has been well served by the Duke of Edinburgh. For any other faults and criticisms that can be laid at his doorstep no-one can deny the sense of duty and commitment he has brought to his role.
He doesn't understand, let alone acknowledge the concept of retirement. For so long as he can walk and talk he will continue to serve. It's a pledge he made back in 1947, following on from his choosing to serve this country during the war. And it's a pledge he has never resiled from.
And it's that sense of duty which also explains why he and the Queen remain so close because, in essence, it has been a joint monarchy for decades.