As was so often the case, he was dutifully by the side of his wife, The Queen, during the momentous occasion for the Northumberland town in June 2011.
Her Majesty and Prince Philip were invited by the Duchess of Northumberland to the town where they officially opened Alnwick Youth Hostel and met local volunteers at Alnwick Castle and The Alnwick Garden.
Then they met the crowds who had lined Bondgate Within during a fabulous walkabout. The Duchess was accompanied by several of her Deputy Lieutenants for Northumberland, including former footballer Alan Shearer and ex-boxer Glenn McCrory.
Here are 15 more pictures of his visit. See the first gallery here.
Then they met the crowds who had lined Bondgate Within during a fabulous walkabout. The Duchess was accompanied by several of her Deputy Lieutenants for Northumberland, including former footballer Alan Shearer and ex-boxer Glenn McCrory.
6. Welcome to Alnwick
The Queen and Prince Philip arrive in a packed Bondgate Within to begin their walkabout. Photo: Michael Pearson
7. Popular Prince
The Duke of Edinburgh heads towards the crowds in Alnwick town centre for a chat and a smile. Photo: Peter Berry
8. Toying with the crowd
Prince Philip entertains the crowds in Bondgate Within in Alnwick town centre. Photo: Peter Berry