North Yorkshire Police said officers were called at around 12.30pm to reports that a woman had fallen through a roof at the Corn Mill on Chapel Street in Skipton.
The woman, believed to be in her forties, was treated at the scene by ambulance staff and taken to hospital by air ambulance. She is believed to have sustained head injuries in the fall.
It's is believed the woman had climbed on the roof via a first floor window.
The route of the Tour de France was not affected by the incident.
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