Five people were injured following a serious head-on crash at Stone Well, near Tanunda, on Monday morning.
At about 9.40am, emergency services were called after two cars collided on Hanisch Road.
Three occupants were taken to the Lyell McEwin Hospital while two were airlifted to the Royal Adelaide Hospital with serious, but non life-threatening injuries.
A group of four people aged in their 60s and 70s were in the first car, while a 30-year-old sole occupant was in the second vehicle.
Barossa Highway Patrol is investigating the cause of the crash which occurred on the crest of the hill on a gravel road.