Police said the 87-year-old had been driving a Red Range Rover Evoque around 14:40 on Friday (20 December) when he “overshot the yellow line at the junction with La Route du St Jean and hit the granite wall opposite”.
“The car went headfirst into the wall and also hit a metal safety barrier,” they added.
All three Emergency Services – Police, Fire and Ambulance – were called to the area, and the pensioner was taken to hospital for treatment to an open fracture on his leg.
Police are now appealing for more information about what happened.
They’re asking members of the public who witnessed the crash to call 612612 or make an anonymous report via Crimestoppers’ online form.