The event marked the end of the 1664 Global Challenge, which recognises 1664, the year the Royal Marines were founded, and has seen marines push themselves to the limit with a series of physical exploits in aid of the Royal Marines Charity.
After decades spent circling the globe, Prince Philip's final official event will take place closer to home, with an audience of Royal Marines gathering at Buckingham Palace.
The Queen's Consort announced in May he would be retiring from royal engagements, a decision which was fully supported by the Queen and was not medically related.
It was initially spotted by Guardian writer Rhiannon Cosslett, who tweeted that it was a "Royal f*ck up".
No discussion of the duke as a public figure is complete without referring to his sometimes idiosyncratic... He has also carried out 637 visits abroad on his own and given almost 5,500 speeches.
She said: "As he carries out his final public engagement, I thank The Duke of Edinburgh for a remarkable lifetime of service".
Philip "may choose to attend engagements alongside the queen from time to time", a spokeswoman said, while stressing that the 91-year-old monarch was not retiring.
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Trump has been at his New Jersey golf resort since Friday evening and was watching the US Women's Open golf tournament on Sunday. Warner called it "very troubling" and said it "obviously moves our whole investigation to another level".
The Duke was wearing his Royal Marines tie and it is thought his large collection of 17 medals and military honours under his raincoat, including his War Medal (1939-1945) with Mention in Dispatches, Atlantic Star, Africa Star, Burma Star, (with Pacific Rosette) and Italy Star.
"He is taking charge of his own life, instead of having private secretaries saying do you want to do this in March, this in April? Every year, he and (his daughter) Princess Anne vie to which of them does more". Gruff in public - he hates media interviews - he is also widely credited for keeping his family together during the turmoil of his children's divorces and the death of Diana, princess of Wales.
The Duke, who is the Captain General of the Royal Marines, met Corporal Will Gingell, 33, and Corporal Jamie Thompson, 31, who have run 1,664 miles over 100 days.
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Prince Philip is still in good health for a man of his age, although he was hospitalised for two nights in June for an undisclosed infection. His sense of humour has got him into trouble in the past, making headlines for politically incorrect jokes.
Prince William, the 35-year-old Duke of Cambridge, ended his two years as an air ambulance pilot last week to turn his full attention to royal duties, alongside his wife Kate.