Scotland’s famous 732-pound Dinnie Stones are so heavy, most strongmen can’t lift them.

A 29-year-old Australian has become the first woman in almost 40 years to do so.

Leigh Holland-Keen, who works as a nurse, completed the “ultimate” strength challenge on Sunday in front of hundreds of people in Potarch, Aberdeenshire.

The granite boulders are so tough to raise that most people who try, fail.

“They are still the ultimate stones,” said Jim Splaine, who hoisted them 65 times. “There’s 50 to 60 (other stones) in Scotland and the Dinnie Stones are the heaviest.”

It’s something Holland-Keen was acutely aware of as she walked up to the boulders to put a year’s worth of training into action.

“Last year was the first time I actually had a go at it,” she told News.com.au. “It wasn’t planned — I traveled over from Australia to Scotland with my stepdad and mom, who also lift, and was given an opportunity to do it.”

Despite not training specifically for the Dinnies, she gave it a crack. She didn’t get them up, but came close enough to realize it was possible.

“I was very close to getting them a good lift, so after that I thought, ‘Maybe I can actually do this if I put in some work.’”

She placed more focus on her grip strength as she continued her strongwoman competitions in Australia.

“My sporting career is in strongwoman, that’s my background, so I have been constantly training for that. But over the past 6-7 months, I mainly focused on deadlifts, trap bar, and deadlift holds.”

The 29-year-old kept her target reasonably quiet, aside from the occasional social media post. “I didn’t want to make a huge deal of it just in case I failed.”

The stones are named after Donald Dinnie, a sporting figure from the 1800s who carried them 17 feet across a bridge in Potarch, Scotland. They are known as the “ultimate” trial of strength for strong men and women, and only 76 people have actually succeeded in the last 60 years.

The last woman was an American in 1979. That was until Sunday.

Approaching the boulders, Holland-Keen was acutely aware of the legends of the sport who were watching and the task she had to perform.

“I was strangely calm. I’m actually a nervous person competing in my sport. I thought, ‘If I do it, it’s fantastic, but I can always come back and try again.’ Not many females have attempted it, so it was pretty special.”

The key to getting them up wasn’t entirely physical.

“It’s mental. Obviously, there’s a lot of training, but you do a lot of visualization on the day. It made me realize how much mental strength it takes to do it by watching these big guys — who I knew could lift it easily — and they were failing because they weren’t there mentally.”

For Holland-Keen, who is a registered nurse, it all came together on the day.

“I was pretty ecstatic. Relieved yes, physically very sore, but mentally I’m feeling pretty good.”

Her mom, Susie, 46, also managed a partial lift of the stones so “that was amazing.”

It was through her mother and stepfather that she got into the sport. She would watch them at competitions and they encouraged her to have a go.

“It’s a constant challenge. You can’t be on top of every sport — there’s always something to work on. But it’s so good to achieve something you work towards.”

People were fascinated when they learned about strongwoman competitions, and especially the Dinnie Stones.

“It’s quite a hard one to explain,” she laughed. “We spent our holiday coming here to lift these huge rocks.”

Holland-Keen said she hoped her feat would help pave the way for more woman to take on the Dinnie Stones.

“Society is slowly accepting females lifting weights and getting stronger.”

The barriers were continually being broken.

“There’s still a common myth that lifting weights you will gain too much muscle and lose femininity — it’s not true, it takes years to build muscle.”

She added: “But it’s good to be strong, it’s badass, and I love it.”