The world's best ski runs: Peak thrills in extraordinary conditions

In an extract from his new book detailing the world's 50 greatest ski runs, Patrick Thorne picks his top pistes for extreme adventure and striking scenery

The sun-drenched, untouched trails of Portillo, Chile (Ski Portillo/Rogier van Rijn)

North America

Mount St Elias, Canada/US

The mountain on the border between Yukon and Alaska is little known and even less frequently visited. The weather is generally terrible, with fog alternating with blizzards the norm, and night-time temperatures frequently at minus 40C. Actually climbing up it, let alone skiing down it, is rarely attempted.

Still, this is the longest possible snow-covered vertical on the planet, going all the way down to sea level, in fact – some 5,488 vertical metres – so someone had to do it, and in 2000 somebody did. Well, most of it.

In May of that year, American ski mountaineers Lorne Glick, James Bracken and Andy Ward made the summit and skied down 3,300 vertical metres over two days to the Bagely Icefield. The team skied down the Mira Face – rather ironically regarded as the "easy route". Lorne Glick would certainly disagree with that description – he later said that the gradient is such that a fall up there, "would be the end, no doubt".

Among the hazards Glick noted is a band of rock about one-third of the way down the slope that is steeper than the slope and about 2.5 metres wide. The trio began the descent partly roped together through a maze of huge cracks in the snow surface beneath the north face.

Two years later, ski mountaineers Aaron Martin and Reed Sanders also made the summit and attempted the ski down. Tragically their bodies are still somewhere on the mountain.

More widely publicised was the successful 2007 descent by Austrian Axel Naglich, and his team-mate Peter Ressman, for a film by Gerald Salmina, entitled Mount St Elias. The duo of world-class adventurers skied most of it, but still didn't manage to descend the full vertical on skis – the bottom 250 metres close to sea level at Icy Bay was deemed unskiable. They had to do it in two separate sections, a month apart, the lower section (about 3,000 metres) in May and the upper section (about 2,000 metres) in the summer.

All of which means that the full, top-to-bottom, 5,489-vertical-metre ski descent of Mount St Elias, the world's longest continuous vertical, is still up for grabs. Will you add it to your "must ski" list? You'd have to be at least as good as Axel Naglich and Peter Ressman, though. No, me neither. nps.gov/wrst

Europe

Pic du Midi, France

On a clear day, the views from the Pic du Midi, the highest lift-served point in the Pyrenees, are truly stunning. There are up to 300km of peaks in view, and it is imperative that you stay a while and take in the 360-degree panorama. Indeed, in clear conditions, the night sky above is equally stunning – Nasa installed its own telescope here in 1964 to map the surface of the Moon ahead of the Apollo missions. It is possible to stay in original (but fully modernised) accommodation at the observatory overnight – where there are raised beds to admire the view of the Pyrenees – and then ski down the next morning. There's also a museum, a shop, a champagne bar and a traditional restaurant at the summit, and the majority of the 110,000-plus people visiting the observatory each year do so to see these attractions, then take the lift back down. You'll have the skiing pretty much to yourself.

So, to the slopes! The Pic du Midi de Bigorre is a perfect pyramid and towers more than 2,000 vertical metres above the Lannemezan plateau. As with the Vallée Blanche, there's a classic route down and many variations thereupon, including longer and steeper options.

The classic route leads you down towards the resort of Barèges, more than 1,000 vertical metres below, with those longer runs (subject to conditions) including the Coume Peak run (1,500 metres) or the Combe de l'Ours (which translates as "Valley of the Bear") that takes you down some 1,700 vertical metres and takes around four hours to complete.

Both of these routes end up in the little hamlet of Artigues. A shuttle bus, the navette de free-riders, will take you back to La Mongie from Artigues.

The classic run begins with a very short and gentle hike up to the sometimes windswept peak before starting your descent.

If it was groomed and graded, this might be a black-gradient slope with those magnificent vistas still in front of you, before it drops into vast, wide, sweeping, powder-filled valleys between rocky buttresses. In normal conditions a good off-piste skier can cope with these and indeed obtain maximum powder pleasure from them.

For the most extreme, there are options en route, including the infamous north-east face, which narrows to a 50-metre cliff that has a ribbon of snow a little more than a ski's width to negotiate. picdumidi.com

Asia

Mizuno no Sawa, Japan

Niseko's snow is the best for quality and quantity combined. The air dries as it crosses the thousands of kilometres of plains that cover the eastern Asian mainland. That air then hits the Sea of Japan, where it sucks up moisture, then rises rapidly as it bounces into the western flanks of the mountains of Hokkaido, Japan's most northerly major island. Here, it dumps vast volumes of light powder. Niseko's average annual tally of 16 metres is not quite the world's biggest (a title held by Mount Baker in Washington State, US) but purists rate Niseko's snow as, usually, better.

Not only is there the powder, there's also the mountain. Mount Yotei – 1,898 metres – dominates the view from the slopes: a visually perfect – and still active – volcano that appears to be a scale replica of Mount Fuji. It hasn't erupted in 3,000 years, but the geothermal activity helps to supply hot water for the various onsen (hot-water springs) in the area – the perfect natural après-ski hot tubs.

The Japanese are less enthralled by all the snow and clear it away efficiently from roads, roofs, lifts and pistes; skiing on it in its uncompressed state has not, historically, been the norm. During the boom years of Japanese skiing in the 1980s, the groomed pistes were filled with determined skiers, but off-piste was against most resorts' rules (minimum penalty: lift pass confiscation). Those resorts that did allow it usually required that you register with the local police station before heading out of bounds.

Niseko's answer is Mizuno no Sawa, a once "permanently off-limits" bowl beneath the Niseko gondola in the Higashiyama sector of the resort. It had long been seen as an attraction by back-country skiers, but the avalanche danger was high and three fatalities had been reported among those who did not obey the warnings. Niseko brought in local and international avalanche experts in 2008 to try something largely unheard of in the country – setting off avalanches manually to clear the danger and open the area to skiers and boarders. niseko.ne.jp

Southern hemisphere

Roca Jack, Chile

It was the Chilean government that first tried to market Portillo as a ski resort. It built the famous yellow hotel at its base and even hired the greatest skier of the time, the Frenchman Emile Allias, to run the ski school. Allias was a former world champion, and among many achievements in his 100 years of life, he developed several great ski resorts around the world. Eventually, in the mid-1950s, the government decided to sell the resort to an American called Bob Purcell, who then brought Portillo up to international resort standards. His family has run it ever since.

On the slopes, Portillo is famed for its advanced terrain and powder skiing (heliskiing is popular) and it has a great sunshine record – four days in every five are sunny. It also still manages to clock up an average of six metres of fresh snow a year. With a maximum of 450 guests in that famous yellow hotel – which maintains the community-style, all-inclusive experience it has offered since the 1950s – the resort is also known for having no lift queues and uncrowded slopes.

Despite all that powder, around 80 per cent of Portillo's runs are groomed every night. These include the popular Plateau trail, the scene of Jean-Claude Killy's win in those 1966 World Championships two years before he swept the board at the Grenoble Winter Olympics (Franz Klammer was also there, and famously forgot to remove his ski boots, or his skis, before taking a dip in the hotel pool). But Roca Jack, arguably Portillo's most famous and most challenging trail, is one of the few marked runs left in its natural state. It was one of the first runs to be created at the resort, and still attracts the world's best teams for training each summer; the Austrian, Canadian, Slovenian, and US teams are regulars.

Located on the Juncalillo side of Portillo's ski area, Roca Jack gets the sunshine early each day. This makes it the first run to soften in the morning sun, so it's a great one to ski first thing. Along with its challenge, the run also offers spectacular views from top to bottom.

A short hike past the top of the lift, you can see the peak of Aconcagua which, at 6,962 metres, is the tallest in both the western and southern hemispheres and one of the "Seven Summits" – the highest peaks on each of the continents. Many other Andean peaks in the 6,000-metre range are also visible, and as you descend the run you have a wonderful view of the Inca lake below, all the way from start to finish. skiportillo.com

This is an edited extract from Powder: the Greatest Ski Runs on the Planet by Patrick Thorne, published in hardback by Quercus (6 November, £25; quercusbooks.co.uk)