The accident happened at around 1pm on Sunday, August 22, when a Honda Jazz collided with a Skoda Rapid on the A87 heading towards Balmacara.
Emergency services were called to the scene and took the 73-year-old woman – who was a passenger in the Skoda – to Queen Elizabeth University Hospital in Glasgow with life-threatening injuries.
The driver of that car, a 58-year-old man, was also taken to the same hospital with serious injuries.
A 55-year-old woman who was a passenger in the Honda was taken to Raigmore Hospital in Inverness.
The road was closed for around 15 hours to allow a full collision investigation to be carried out and Police Scotland officers are now appealing for information to assist in the investigation.
They are particularly keen to hear from anyone with dash-cam footage from the area at around the time of the accident.
Sergeant Ewan Calder, of Fort William Road Policing Unit, said: “This has been a serious crash and our enquiries are ongoing to establish the full circumstances surrounding the incident.
“I would ask anyone who was driving in the area at the time and may have seen either car prior to the crash or anyone with dash-cam footage that may assist with our investigation to get in touch with officers.”
If you have any information on the accident you should contact Police Scotland on 101 and quote incident number 1969 of August 22, 2021.