A proud shoe designer will be keeping an eye on the King's feet during the coronation - as the monarch sports a £3,500 pair of handmade pumps made by his firm.
Gaziano & Girling, founded less than 20 years ago, has been supplying the King since he visited its headquarters in Balfour Street four years ago.
Watching on proudly with his family will be creative director Tony Gaziano.
Last month Mr Gaziano, 50, and his business partner Dean Girling were told the King had chosen to wear their shoes for the ceremony in Westminster Abbey which will be beamed around the world.
He said: “Basically the King is going to be wearing our shoes for the coronation, which make us immensely proud, so it's going to be a great day for us."
Mr Gaziano said everyone at the firm had been thrilled when they heard the King would be wearing the pumps, which were made for him last year.
"The whole factory is buzzing, incredibly proud and incredibly proud to do it for the county and for English shoemaking," he said.
"His Majesty is a great fan of British craftsmanship so he really wanted to keep it in the UK and we're just fortunate that we're the ones he has chosen."
The shoes are made from leather created from calves which graze in a specific part of the Swiss Alps.
While they might sound expensive at £3,500, the firm makes handmade shoes that cost considerably more.
"A lot of the bespoke shoes we make are between £4,500 and £5,000 and we've even made shoes that go up to £20,000 a pair," Mr Gaziano said.
Bespoke shoes can take 12 months to make. Clients have their feet measured and a wooden model - known as a last - is carved to match the foot.
Sometimes three pairs of shoes are made for the customer to try on before the final shoe is crafted.
Mr Gaziano said: "It's made in the way shoes were made 200 years ago: completely by hand, no machinery whatsoever.
"[It takes] probably 96 hours of constant labour in making these shoes so it's a very rare craft these days."
Mr Gaziano said fitting the King had entailed visits to parts of Clarence House and Sandringham that the public would never see.
He described the King as a "pure gentleman" and a kind man.
"He's really nice and a very clever guy. We're never rushed when we're there, he gives us all the time we need and always asks us about our families and how we are doing in life.
"He's got a lot of time for people."
He said he would be glued to the TV on Saturday, which was also his daughter's birthday and the family would be having a double celebration.
"I'll probably be watching his feet more than him on the day, to be honest, to see if we can get any good screen shots of him wearing them," he joked.
His business partner Mr Girling, 53, will be watching from the US where he is on business for the firm.
The pair have both been making high-end shoes in England for more than 30 years but went into business together in 2006.
That makes Gaziano & Girling the new kids on the block in Northamptonshire, the historic heart of British shoemaking, after just 17 years in business.
Mr Gaziano said the King liked the factory when he first visited in 2019.
"He chose to visit the oldest and youngest shoe factories, the oldest being Trickers and the youngest being us," he said.
"He liked the fact that we employed a lot of young people, that we had trained young people. He liked the fact we were the first factory to open up in over 100 years and we had brought back an age-old tradition that the King is very interested in."
Northamptonshire has been described as the shoemaking capital of the world, with a tradition of the trade going back centuries.
The county benefited from a plentiful supply of oak bark and water for tanning, plenty of leather from cattle markets and a central location for trading with the rest of the country.
Northampton Town's football team are still known as the Cobblers.
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