‘The most aesthetic line’: how Kilian Jornet climbed the seventy-three highest US mountains in one month

While I stood for the sun to appear over Colorado’s Front Range, adjacent to the sprawl of Denver–Boulder–Fort Collins, a west wind gusted, sending a chill down my spine. In temperatures around freezing on a granite shelf at 13,700ft, I looked for reprieve on the protected side of a stone formation.

Separating us lay a expanse of granite rock, known as the Cables climb. This is the straightest way to the summit of the Longs summit, but is less travelled because it’s classified a class 5 rock climb and often has a river of glaze ice – slick ice – running down it, which alpinists must navigate.

In this way I began the first morning of the athlete's latest physical feat, Elevation States. In it, he would summit the tallest 73 mountains in the contiguous US – each summit above 14,000 feet – all under muscle power, biking between and climbing each one.

Generally acknowledged as the greatest alpine sportsman of all time, he grew up in a mountain refuge, a mountain hut in the Pyrenean range of north-eastern Spain. His father who worked as a alpine guide and a mom as a educator, the athlete summited his first peak before the fifth birthday.

Over his two-decade career, Jornet has established fastest times on Mount Aconcagua, the the Matterhorn peak, Denali, Africa's Kilimanjaro and the Everest summit; won the three major events of long-distance racing – the Western States race, Hardrock and the UTMB race – and dominated mountain races, with ten victories at the Sierre-Zinal race and over a decade of victories at the Zegama race.

Regardless of his achievements, he remains soft-spoken and modest. While his racing success has bolstered his professional life and helped him accumulate almost 2m Instagram followers, he’s wary of notoriety, telling me that many of his favourite days are personal expeditions in the mountains.

Longs Peak was the beginning of a journey that would take him over 3,000 miles of travel across multiple states, concluding on Rainier Mountain in Washington State. Simultaneously, my assignment – outside of joining Jornet for a peak here and there – was to write about the adventure openly, without excessive use of exaggeration to endorse his extraordinary accomplishments.

Before dawn I began ascending, an hour before Jornet and fellow climber, the current record-holder on Longs Peak, started their ascent. Now, from my vantage above Cables, I watched the two climb skillfully across a segment known as the Boulder field and begin the difficult ascent.

When they approached, I could hear them talking easily about past adventures, like longtime companions on a recovery run. Challenging alpine climbs, icy conditions and winter conditions is where he feels in his element, and where he radiates the most joy.

On the top of Longs, Jornet paused to take out his phone and snap a few photos, which he would later send to his wife, Emelie, also a professional mountain-runner, and their three young daughters. Even though it seems that Jornet’s life is focused on chasing the edge of possibility, nothing is more important to him than his household.

In his view, this achievement had been years in the making. Two years prior he climbed all 177 3,000-meter peaks in the Pyrenean range in just 8 days. The following year he climbed all 82 4,000-metre summits in the European Alps in 19 days, using only human power to link them.

This constituted the optimal blend of his interest about the body’s limits and a drive to understand risks to American wilderness, through both direct encounter and conversations with inhabitants along the way.

Upon reaching the Longs summit, he could have turned around, run down, and cycled to the subsequent mountain, saving time and considerable energy. Conversely, he opted to traverse the 38-mile long Freeway path, an cross-country course with 21,000 feet of ascent and descent, which took him the remainder of the day.

He is a simplicity advocate who often goes hours without food or water. He’s an environmental advocate who believes in protecting pristine environments. His expertise in technical terrain that it comes as effortlessly as moving on foot.

By the third day with Jornet, as we scaled the Grays summit in the evening as the tail end of a lightning storm passed through, I inquired about his motivations. He elaborated it had nothing to do with velocity, records, or even anyone else knowing about it.

For the athlete, the peaks are a essential requirement. He wanted to witness the isolated peaks of Colorado's wilderness, appreciate the vastness of western landscapes, and grasp the steep terrain of the volcanic peaks, because immersing himself in these environments gives him life.

Shortly after, he completed the Elks journey, a 50-mile long difficult climb near Aspen, Colorado that has only seen a handful of finishers. Subsequently he finished Nolan’s 14, the state's most notorious fourteener link-up, with just a half-hour rest in between.

As my time concluded in the state, I hiked up the less-traveled route of Mount Massive and joined the athlete near the top. Dusk had fallen and the sky was becoming a misty blue as the remaining daylight faded.

He,