The 90-year-old Balclutha woman entered the Southern Motorway via the Abbotsford exit at Westland St and drove more than a kilometre the wrong way before her vehicle collided head-on with another vehicle about 6pm on Sunday.
Dunedin road policing manager Senior Sergeant Phil McDouall confirmed the woman had her full licence.
She remained in Dunedin Hospital with extensive fractures and faced a ''long and unclear journey to recovery''.
He said the three people in the other car also remained in hospital, all in a stable condition.
The adult male driver suffered a serious leg injury, his adult female passenger a broken collarbone and a broken arm and her 5-year-old niece required surgery for internal injuries.
The serious crash unit is investigating.
