The A11 at Besthorpe was shut for more than two hours on Tuesday afternoon after a car hit the central reservation.
The incident happened on the Norwich-bound carriageway shortly after 2pm, and involved a Ford Mondeo.
Norfolk Fire and Rescue Service, the East of England Ambulance Service NHS Trust and Norfolk Police all attended the scene.
No one was trapped or seriously injured.
The road was clear again by 4.30pm.