Jo Needham was halfway through a "bucket list" trip across South America when she was flung from her seat on a train leaving Machu Picchu in Peru.

The Australian said she was prepared for flight delays or cancellations, and for stolen or lost luggage, but had never imagined she would be caught up in a train crash.

"Never in my wildest dreams would I have expected to be involved in such a huge accident," the 45-year-old told the ABC.

"I'm still in a bit of shock now."

Jo Needham on board the train to Machu Picchu. The crash happened on the way back. (Supplied: Jo Needham)

Two trains, one run by PeruRail and the other by Inca Rail, collided on Tuesday, local time, in a head-on crash that killed one of the train's drivers.

The Peruvian health ministry said 104 people were hospitalised and 53 had already been discharged. Two people were receiving specialised care for severe injuries.

The Australian Department of Foreign Affairs and Trade said it had spoken to five Australians on board the two trains, none of whom were seriously injured.

Ms Needham said she felt lucky to walk away with a few scratches on her arms and whiplash.

"I was on the train having a great chat with the people sitting opposite me, a couple of guys from South Africa, talking about travel and what adventures we were having," she said.

"Suddenly, you heard both train whistles going, really loud whistles, and I was just kind of flung forward from my seat.

"My elbows took a lot of the brunt."

Everyone in her carriage, she said, helped one another bandage wounds and collect dropped phones and scattered luggage.

"It was a bit chaotic then because nobody really took charge, and you didn't know what was happening, and anything that was being said was being said in Spanish."

A train driver died and passengers were injured in the head-on collision. (Supplied: Jo Needham)

After roughly 15 minutes, she said, passengers got off the train and walked along the tracks, hauling luggage and helping the injured over loose rocks towards the closest station, which she guessed was about 300 metres from the crash site.

"They sent another train to pick us up because there's no way in by car where we were. We had to get on the train, which was a bit nerve-racking after that experience."

The passengers travelled to the closest area accessible by road, where ambulances picked up those who were seriously injured.