The 21-year-old Israeli woman, whose name has not been released, was taken to Dunedin Hospital at 12.20pm by the Otago Regional Rescue helicopter.
Her injuries were not life threatening.
Sergeant Ian Kerrisk, of Alexandra, said the woman and her 23-year-old Israeli male companion were travelling in a campervan from Roxburgh to Alexandra.
They stopped south of Shingle Creek to take photographs.
The woman was hit by a Honda Civic car being driven towards Alexandra by an 18-year-old Invercargill woman at 11.20am.
"She stepped out on to the road from in front of the campervan, where she was obscured, and was hit by the car.
''She went on to the windscreen of the car and was then thrown on to the road.
"She's incredibly lucky she was not killed," Sgt Kerrisk said.
He said the 18-year-old driver and her 18-year-old female front-seat passenger, also from Invercargill, had seen the parked campervan and the male tourist standing at the back of the vehicle as they drove around a corner.
"Luckily, the driver slowed down considerably from the 100km speed limit, but there wasn't enough time for her to react when the female tourist stepped in front of the car . . . we are satisfied that there's no fault on the driver's behalf," he said.
Sgt Kerrisk said both Invercargill women were "extremely shaken" and were taken to Alexandra by Victim Support staff.
Police would not take the matter any further, he said.
State Highway 8 was closed until 12.30pm, when one lane was opened to allow the estimated 200 waiting vehicles to travel through.
Sgt Kerrisk said the highway was fully opened by 1pm.
