“Crampons on here. And, err, try not to slip on this section.” Kenton Cool’s casual tone and wry grin make light of the severity of the thin, snowy ridge carving a wicked line towards the Weissmies, a peak in the heart of the Swiss Alps. It’s half a foot wide at most and bloody terrifying, to be totally honest.

Keeping focus is easier said than done at an altitude of 4,000m – the silky air puts stamina under the pestle and makes the simple decidedly complicated. The ridge looks a little different to a tightrope. Not even the endless massifs to my left and right, sprayed with the sun’s early golden glow, can distract me while I’m edging towards the white, pristine plank. Saying that I am in very safe hands: Kenton is Britain’s most decorated climbing guide, having successfully summited Everest an incredible 12 times.

His competence at altitude is hugely reassuring – over the past two days I have put my trust firmly in his aptitude, and (at this very moment) the three metres of rope dangling between us. (It’s a far cry from the cosy Soho bar where, four months earlier, we had excitedly ignited the idea of this trip over a few drinks.)

With our crampons fastened we push on slowly, Kenton’s spikes cutting a fresh trail in the soft, precarious powder. I place mine meticulously into exactly the same grooves, my mind focusing on mastering the basics of balance, channeling my inner Philippe Petit. The margins of error are absolutely tiny when climbing. One mistake, one misjudgment, one gulp of arrogance is all it takes to fail. Or worse. A wrong move here and it will be a fast, fatal journey to the bottom.

Danger and risk are intrinsic to this sport; a sport where men and women are totally at the mercy of elements that are well out of their control. But like a powerful drug, the sacrosanct feeling of success or indeed failure in the mountains is an unreachable itch that most climbers never shake. Kenton knows this all too well.

“You leave knowing that there is a chance you might not come back,” he admits. “That it could be your last climb. If you become complacent at altitude, the mountain is going to kill you. But when you get to the top, the whole world radiating beneath your feet, there’s this tsunami of overwhelming emotion.

“I would defy anybody to witness some of the views I’ve seen and not come away feeling inspired.” Challenge accepted… It had been an early start of 3.45 am for a basic hut breakfast of dry bread and robust black coffee. The aim was to reach the peak, or the ridge at least, to watch the sunrise over the Pennine Alps. “It’ll be worth it,” Kenton assured me as I threw my pack over my shoulders and stepped out into the bitter cold. A heavy fog was hugging the ground, reducing visibility to only a few metres.

“I would defy anybody to witness some of the views I’ve seen and not come away feeling inspired.”

For two hours we clambered up the steep, craggy mountainside by the light of head torches, a deafening silence broken only by the crunching of rocks under sleepy soles. We emerged from the haze as the first inky tendrils of morning teased the skyline – here, just shy of the saddle point, we got a glimpse of the summit, a black silhouette towering into the star-studded ether.

Several thousand metres below in the canton of Valais, two hours from Geneva, the municipality of Saas-Grund was still sleeping. By day it is equally as somnolent, but charmingly so. Timber cabins sit on mushroom stilts, window sills are adorned with vibrant flowers, and the neck-bells of sheep herds resonate above the trickle of glacial streams and the splutter of tottering tractors scything tall summer grass.

There is an intoxicating absence of urgency – such folly is left to those at higher climes. As the skiing masses flock to these slopes in winter, so too alpinists take advantage of Switzerland’s dramatic ranges in the warmer months – the country is home to more 4000m peaks than any other in Europe, from leisurely strolls that wouldn’t strain your grandmother to torturous technical routes suited to only the most adept.

Yesterday we had tackled the frozen northern bluff of the 4200m Allalinhorn, hiking through serac blocks and setting three ice screw pitches to scrabble up the 50-degree face with two axes – a hard-and-fast initiation to ice climbing.

By contrast, this morning we’re on the 4017m Weissmies – lesser in altitude but more physically demanding – featuring nervy scrambling and glacier traversing. There were anxious moments as cold fingers clawed longingly at uninspiring rock ledges and unstable feet searched frantically for safe holds, but with each successful haul the view got that bit better, the summit got that bit nearer, and the acute feeling of triumph and an end to the pain drew closer. Until we negotiate the ridge, that is.

Never have more cautious steps been taken – I was like a tipsy waiter carefully carrying a tray of delicate crystal-cut champagne flutes. Once safely across, we make the final few strides to the top, where we rest, short of breath from the dearth of oxygen. In every direction, scarped snow-capped peaks puncture the cloud inversion, and way down below the quiet valley towns are gradually waking up – it’s not yet 9 am.

Up here, I appreciate the pull to these heights: the early starts; the stale bread; the willingness to pillage one’s senses in order to summit; and the somewhat selfish risk of being a mountaineer. “You know, time is the most precious commodity we have,” says Kenton, flicking sweat from his forehead, “and the mountains allow you to escape all the crap. I can be physically exhausted when climbing, but mentally I’m never more alive.”

Sitting here, gasping for deep gulps of air, I get it. It all makes perfect sense.