Police are seeking witnesses to a single vehicle crash on Mount Ainslie on Saturday night.
Walkers found a 20-year-old man near his vehicle in a gully off Mount Ainslie Drive about 7am on Sunday.
Police believe the crash happened about midnight on Saturday when the man failed to negotiate a bend.
The man, who was the only person in the car, was discovered by walkers the next morning.
He was transported to Canberra Hospital with serious but non-life threatening injuries.
Police have asked for witnesses or people with dash-cam footage of the incident to contact Crime Stoppers on 1800 333 000, quoting reference 6350384.