A driver was taken to hospital after her Vauxhall Astra overturned on the A1(M) at Stevenage.
The Astra left the southbound carriageway at around 5.45am today (Thursday, April 7).
It overturned, and came to rest on a roadside verge.
The crash took place between junctions 8 (A602, Stevenage North) and 9 (A602, Stevenage South).
Officers from Hertfordshire Police were called to the scene.
A police spokesperson said: "Police were called at around 5.45am following a road traffic collision on the A1(M) southbound, near junction 8 for Stevenage.
"Officers attended, alongside colleagues from the fire and ambulance services and a lane closure was put in place.
"The female driver was safely removed from the vehicle and was not believed to have been injured, but was taken to hospital as a precaution."
One lane out of two was closed, but both lanes are now open and the road is clear, Traffic England reports.
The East of England Ambulance Service sent a Hazardous Area Response Team (HART), an ambulance and an ambulance officer to the patient.
"One person was taken to Lister Hospital, Stevenage for further care," an ambulance spokesperson said.
There were delays of approximately 30 minutes on the route, with queues back to junction 9 (A505, Letchworth).
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