The Portes du Soleil ski area bills itself as "the largest internationally linked ski area in the world" – a borderless playground for winter sports lovers.
swissinfo took a look at the ups and downs of cross-border collaboration in the huge region straddling Switzerland and France.
This year the gods have smiled on the Portes du Soleil. Early snow in November and December means that most of the 14 resorts that make up the ski region have been able to open several slopes early.
"But people don't realise the Dantean work involved in preparing the runs," complained Raymond Monay, in charge of the lift systems at Champéry in Switzerland.
At the top of Mossettes lift, skiers who have been able to take an early break zip back and forth easily between the two countries.
"What is great is that as a tourist you don't see the border. You have the impression that it doesn't exist," said David Rollier.
Forty years since its conception, the region has managed to turn the border and the vision of the original founders into a key marketing tool.
"The Portes du Soleil is an invitation to travel – to go somewhere else," oozed Bruno Gillet, director of Portes du Soleil.
Despite the obvious contrasts between resorts such as the futuristic Avoriaz and the more traditional Champoussin, for many tourists there are no major differences between the Swiss and French sides. Except perhaps the difficulty of the runs, snow conditions or currencies – Swiss franc or Euro.
But Gillet acknowledged that keeping the chain of ten lift companies and 14 resorts together to ensure a coherent product represented a real challenge.
"There is a trend for each resort to wave its village flag," he said.
And unbeknown to many of the visiting tourists, political and cultural differences either side of the border continue to create distortions.
"The French have understood how to exploit tourism," explained a Swiss ski guide. "Whereas it's always a nightmare to build any new lifts or to develop the resorts on the Swiss side. The environmental groups WWF and Pro Natura always oppose the projects."
Plans to build a new chairlift between Morgins and Les Crosets in Switzerland are on hold owing to differences between the local communities, environmental groups and developers.
Monay admitted that Champéry had "attained its development potential" and could only modernise existing equipment, which took a long time because of strict Swiss regulations.
"The problem is the gap is widening between Switzerland and France," he warned.
One possible consequence might be that people stay more in France, creating an imbalance in ski traffic and in the sharing-out of income earned from ski passes bought in the Portes du Soleil – estimated at SFr70 million ($60.5 million) in 2006.
Another distortion is caused by the profile of tourists to the region: 80 per cent on the Swiss side are day-skiers, whereas big tour operators mostly fill the French resorts.
The Swiss resorts have therefore become extremely dependent on the weather conditions. "If we get bad weather one weekend, we take a real beating," said Monay.
A further problem for the Swiss side is the proliferation of luxury holiday homes, which are rarely rented out and only inhabited a few weeks a year.
The Swiss resorts are hoping that cantonal regulations making it harder for people to build holiday homes, and a greater focus on new hotel beds will help them catch up with their French neighbours.
Back on the slopes, as the morning sunrays slowly melt the crisp new snow, the development and cross-border worries seem miles away.
"They've managed to make the border disappear. It works really well," said Rollier, clipping on his skis and disappearing back into Switzerland.
swissinfo, Simon Bradley in the Portes du Soleil
The Portes du Soleil, comprising 14 resorts between Lake Geneva in Switzerland and the Mont Blanc in France, is the largest internationally linked ski area in the world.
The area offers 278 ski runs stretching over 650 kilometres.
The 14 low-level resorts that make up the Portes du Soleil are: Champéry, Champoussin, Les Crosets, Morgins, Torgon and Val d'Illiez in Switzerland, and Abondance, Avoriaz, La Chapelle d'Abondance, Châtel, Les Gets, Montriond, Morzine and Saint Jean d'Aulps in France.
Portes du Soleil
Until 1815 – when canton Valais joined the Swiss Confederation – the villages that today make up the Portes du Soleil were all part of the Duchy of Savoy.
The Portes du Soleil cross-border ski area dates back 40 years and takes its name from a mountain pass just above the Swiss village of Les Crosets.
In the 1960s a group of Swiss and French promoters and ski enthusiasts - including Jean Vuarnet, gold medallist at the 1960 Winter Olympics in Squaw Valley - came up with the idea of linking the ski runs of Les Crosets and Champéry in Switzerland with neighbouring French areas, particularly Avoriaz.
The foundation of the area was laid in 1956 with the Corbeau draglift, which linked Morgins to Super Châtel. In 1964, a model showing the relief of the area and the proposed links was displayed at the National Exhibition in Lausanne.
The Avoriaz-Champéry-Les Crosets lift pass was introduced in 1969 and the main links needed to launch a single Portes du Soleil pass were in place in 1976.
Despite the borderless concept, skiers crossing into France or Switzerland are still subject to occasional identity and customs checks on the slopes by plain-clothes police officers.