A stretch of the A1 in Northumberland was closed after a two-vehicle crash on Tuesday.
Police received the call at 12.30pm following the collision involving a van and a car on the southbound carriageway near to Burgham.
Firefighters and paramedics were also called out.
Michael Smith and his fiancé Beverley Williams, both retired front-line London Ambulance Service staff, were travelling from Seahouses to Dover and they arrived at the scene not long after the incident.
They helped the driver of the van, a Mercedes, out of the vehicle.
A police spokesman said no-one was seriously hurt.
Mr Smith said: “The van was on its side with the driver inside and it was blocking the whole carriageway.
“Two members of the public were holding the door open and after the firefighters took out the windscreen, me and Bev were able to help them get the driver out of the vehicle.
“He had a cut to his head, but thankfully he didn’t have a serious injury.
“The front ends of both vehicles were very badly damaged and we checked out the lady driver of the car, who was shaken up but not badly hurt.”