In the testosterone-drenched fraternity of mountaineers, Diahanne Gilbert is a refreshingly unexpected sort of leader. No faintly colonial bragging from behind ice-beaded whiskers here. Instead I’m sipping tea at the home of a cheerful blonde Aberdonian whose only obvious link with the world’s tallest peak is the hint of residual windburn on her cheeks.

It’s barely a month since this 31-year-old became the first British woman to lead an expedition to the top of Everest. Her 21-year-old English client, Jake Meyer, got most of the publicity, becoming the youngest person to conquer the highest mountain on each of the seven continents — not to mention the youngest Briton to scale Everest.

But in many senses Gilbert’s was the more impressive achievement. While her fellow Scotswomen Polly Murray and Vicky Jack had both previously claimed the 29,028ft peak, neither led their expedition, nor had the added responsibility of looking after such a young climber. Typically, as Meyer broadcast his euphoric achievement by satellite phone from the roof of the world, Gilbert was more hard-headed: most deaths occur on the way down.

“Jake was phoning his parents, breaking down, crying, and I was saying, ‘Don’t cry, your tears will freeze and then you’ll be in trouble’, recalls Gilbert, with a grim chuckle, from the safety of her flat in Grantown-on-Spey. “In hindsight it was bloody awesome, but at the time it was, ‘Okay, we’ve got here, now we’ve got to get back down’.”

As if to remind them of the odds stacked against them, the pair had discovered the frozen body of a climber just yards from the final summit pyramid. “It was a Slovenian guy I knew from base camp,” says Gilbert, clearly distressed by the memory. “He was lying at the side of the path, literally on the rope, a pretty gruesome death. I didn’t want to look. I just blasted on past him, towards the summit.”

Corpses are an occupational hazard on the upper reaches of the world’s highest mountain, where extreme weather conditions and lack of oxygen preclude a burial. The old guard would probably say it’s no place for women. But Gilbert is up there with the best of them, fraternising with Sir Ranulph Fiennes, whose own Everest attempt was aborted because of breathing problems.

Having first climbed as a 14-year-old cadet in the Air Training Corps near her home town of Alford, Aberdeenshire, she set up her own mountaineering company at 23. Gilbert has the kind of tomboyish charisma you might expect from a female pioneer in a traditionally male preserve. She is marked as a “woman with altitude” by one of the forest of congratulations cards on her mantelpiece.

“It’s not a very glamorous job,” insists Gilbert, whose shelves bear souvenirs from climbs in Peru, Tanzania and Antarctica. “I expect to live in a tent for months on end and pee into a bottle with some guy I’ve hardly met right next to me. Because I’ve been trained and educated in a male environment I don’t think anything of it. It’s part of the life.”

She resolutely avoids the macho risk-taking that can become fatal at high altitude. It was why the company Adventure Peaks hired her to lead their April expedition — a leader of proven competence whose bubbly personality works wonders in bonding small groups.

“Jake is a competent mountaineer in his own right, so I never had to babysit him,” says Gilbert. “But at 21, he’s just about to start life, so I wasn’t going to take a chance with this guy. I do push the boat out sometimes, but there’s no macho element. I’m a very safe climber. If I’m not happy in a situation, if things don’t feel right, I’ll put my hands up and say I’m not doing it.”

The strategy proved frustrating at times as the pair dug in for the long haul in subzero temperatures at base camp, waiting for the crucial fair-weather window between gales and the approaching monsoon.

“I’ve never spent so long doing absolutely nothing,” laughs Gilbert, who confesses to having watched a DVD of the film Dodgeball five times in the cramped tent at 20,997ft. “At that altitude you can’t eat, you’re getting headaches, you can’t sleep. It’s like the mother of all hangovers.”

Suitable weather proved elusive, and other teams set off in less than perfect conditions, but she held back. Finally the pair saw their opportunity. “It was our last chance — we had to go for it.”

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