All were members of the ANU Mountaineering Club and used to climb the campus buildings to hone their skills. No wall was off limits, from the library to the Acton Underhill.

"There's a lecture theatre called the Haydon Allen Tank which has insert bricks so the challenge was trying to traverse them. And it was really hard actually," McCartney-Snape said.

"Not encouraged by the university maintenance people."

The young men were among 15 members of an ANU expedition which in 1978 attempted to climb Dunagiri, a 7066m peak in the Indian Himalaya.

Just six years later, Macartney-Snape would become the first Australian to reach the summit of Mount Everest. Lincoln Hall, a Canberra boy who went to Telopea Park High, was also part of that 1984 expedition to Everest.

But before then, on the Dunagiri expedition, they were accompanied by The Sydney Morning Herald journalist Ben Sandilands, who captured many images of the trip. Nugget Coombs, a former ANU chancellor among his many roles,helped open doors to allow the trip to happen, including the sponsorship of Fairfax.

"The ANU were incredibly supportive of the expedition and put a lot of resources into it," Ken Baldwin said.

The Dunagiri expedition turned out to the be first ascent by an Australian of a plus-7000m Himalayan peak and proved to be life-changing for all, particularly Macartney-Snape and Hall who both went on to conquer Everest and make a career from mountaineering.

Three of the original 15 including Hall and Sandilands have since died. Seven of the original group gathered at the ANU on Friday night to celebrate the 40th anniversary of the Dunagiri, joined by other guests and mountaineers.

"In retrospect, it was too ambitious,"Macartney-Snape said, of the 1978 expedition. But they had the enthusiasm of youth on the side.

"When you're young, you think you can do anything," Ken Baldwin said.

There was no internet to check climbing conditions. No proximity to very high mountains. New Zealand had been their training ground. Dunagiri was their first attempt at climbing at real altitude.

"It was kind of the Australian way to cobble things together and jump in and, in the end, we were lucky. Nobody died," Macartney-Snape, 62, said.

In the end, only Macartney-Snape made it to the top. "Stubbornness" was what got him there.

He and Hall had made a dash for the summit of Dunagiri. Macartney-Snape reached it, on May 18, 1978. Hall stopped about 150m from the top. Both were caught in a storm on their descent. Hall was airlifted off the mountain by an Indian army helicopter. He lost parts of toes due to frostbite. (Ten years later the Indian army sent a bill to the ANU sports union for 11,000 rupees, about $200, for the airlift. That sparked the first reunion of the climbers and a chip-in to pay the bill.)

Macartney-Snape, who lives in the Southern Highlands, said the Dunagiri, expedition was a massive learning curve for them all, from the logistics to the conditions. He had no idea he and Hall would go on to scale Everest.

"Back then, Everest was totally off the radar," he said, adding the Dunagiri trip was "a turning point in my life".

"It was the beginning of a lifelong affair with that part of the world," he said.

Lincoln Hall made it to the top of Everest, in 2006, surviving a world-famous, near-death experience on his descent. He died of mesothelioma in 2012, aged 56.

"Obviously when someone dies at a relatively young age it's very sad, especially for their family," Macartney-Snape said. "I can't help thinking the trauma he experienced on his climb of Everest may have triggered something, we really don't know."

Forty-years later, Ken Baldwin, 63, now a professor of physics at the ANU, said the Dunagiri expedition had a profound impact on them all.

"You gain confidence from having done something like that which actually transfers over to other endeavours and I think that was the great thing about the trip," Professor Baldwin said.

"It changed the way I thought of myself and my limits and how I could overcome my limits."