A "disoriented and confused" crash victim plummeted into a quarry after wandering away from his vehicle in a daze, police have said.
The man fell from a "significant height" at the site near Yate, South Gloucestershire, at about 04:10 BST.
He was tracked down by a police dog, and airlifted to hospital after firefighters carried out a rope rescue.
Officers praised PD Nerf for finding the man so quickly and "likely saving his life."
Avon and Somerset Police were called to Wickwar Road to find a white Mercedes Sprinter van on its side.
"The man was thankfully quickly located having fallen into the quarry," a police spokesman said.
"It is believed he was left disoriented and confused following the incident, walking away from the vehicle," Avon and Somerset Police said.
The spokesman said the man was in a serious but stable condition.