The accident happened about 2.6 kilometres west of the Loddon River Bridge, in a section of road that has seen three fatalities in recent years, including the 2011 death of Illawarra Stingrays player Ashleigh Conner.

The section of road, marked at several spots with memorials of flowers and crosses, was identified as the most dangerous along Appin Road in a 2014 Roads and Maritime Services report.

Friday’s accident occurred shortly before 7am when an eastbound silver Commodore driven by a 25-year-old man collided head-on with a bronze Rodeo ute driven by a 22-year-old man in the opposite direction.

The two men were the only occupants in the cars.

The 25-year-old was trapped in his car for more than an hour before emergency services were able to extricate him.

He suffered significant lower limb and pelvis injuries and was airlifted to St George Hospital in a critical but stable condition.

The 22-year-old suffered head and pelvic injuries and was flown by helicopter to Liverpool Hospital, also in a critical but stable condition.

A police crash investigation team is investigating the crash.

The accident saw the closure of Appin Road for most of the morning, with light traffic diverted along Picton Road.

At about noon, both eastbound lanes and one westbound lane were re-opened to traffic.