The King took the opportunity to climb on board the engine room of the Flying Scotsman as the Royal Train was pulled into a station by the famous steam locomotive.
Charles chugged into the market town of Pickering after a trip through the countryside on the North Yorkshire Moors Railway, which is celebrating its 50th anniversary.
Despite wearing a light-coloured suit, the royal visitor accepted an invitation from the crew, including driver Chris Cubitt, to step onto the footplate of the 100-year-old engine to see how Flying Scotsman works.
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After leaving the station, the King was greeted by hundreds of well-wishers as he worked his way through the centre of Pickering on an extended walkabout, asking many of the schoolchildren who had gathered to see him whether they had enjoyed the half-term break.
Temperatures soared in the baking sunshine and one woman in the crowd appeared to faint just after Charles passed her, falling through the barrier just a couple of metres from where he was talking to the crowd.
The King turned and looked concerned for a moment as one his protection officers and his equerry moved to help her before a number of North Yorkshire Police officers stepped in.
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