Police are appealing for information about a collision between a pedestrian and a red Peugeot on a Greenwith Hill, Perranwell Station near Truro on Saturday 5 December.
The collision occurred on the narrow rural road at around 9am. Police, fire and ambulance crews attended the scene and a woman was taken to hospital with serious injuries.
The road was closed for several hours while officers conducted an investigation at the scene and police would like to thank the public for their patience.
A 51-year-old man from Penryn was arrested on suspicion of failing to stop after an accident, drink driving, dangerous driving, and driving without insurance and bailed until January 1 pending further enquiries.
Any witnesses, or anyone who was in the area at the time and witnessed the driving of the vehicle involved before or after the incident, or has relevant dashcam or CCTV footage, is asked to contact police on 101 or via email at email@example.com quoting log 197, 5/12/20.