Sunglasses on his head and cold beer in hand, Stuart Block looks the very picture of holiday cool. “This is what it’s all about,” he says, gesturing at the spectacular view of Mont Blanc from his two-bedroom flat in Chamonix. “I feel very lucky to be here.”

A self-confessed adrenaline junkie, Block, 28, gets his fix in two ways: at work as an economist for Citigroup and, more pleasurably, skiing off-piste. He also has a sharp eye for an investment. Since he bought his £165,000 chalet apartment in the French ski resort in July 2005, its value has risen by 28%.

“It’s not just a hobby, but an investment,” says Block, who has skied for 20 years. “I chose Chamonix because it is more of an all-year-round resort and has a good nightlife. We are within walking distance of Chamonix town centre.” And within staggering distance back.

The flat is perfect for a work-hard, play-hard man like Block. It has underfloor heating, underground parking, and while it’s not exactly luxurious, its wooden interior is tasteful, functional and more spacious than anything available for the same price in Britain. Rather than buy at home, he would rather rent in London and get more value for money — and fun — by buying abroad.

“I try to go out to Chamonix as much as possible,” says Block. “In winter for off-piste skiing, and in summer for mountain-biking, kayaking and, next time, paragliding.” When he’s not using the apartment himself, he rents it out via his website, www.montblock.com.

Britons have been flocking to this bustling town in the French Alps ever since William Windham and Richard Pococke first explored the area’s ice fields in 1741. But in the past few years, demand for property here has soared, led by young City workers whose spending power, thanks to big bonuses, has driven up local prices. The latest figures published by local notaries reveal that prices for flats rose by 42% between 2002 and 2005.

“The demand has been incredible in the past five or six years,” says Joanna Yellowlees-Bound, chief executive of Erna Low, a long-established holiday company that branched into estate agency in 2003 because of growing interest from British investors. “Most of our buyers are already fairly knowledg-able about ski resorts, are from reasonably wealthy backgrounds and have good jobs in the City,” she says.

“Buyers are just as savvy about their investment as about their skiing. Some people may have taken a punt on lesser known resorts in countries such as Bul-garia and Slovenia, but they are returning to the Alps in droves. In some cases, especially with younger buyers, having a good nightlife is very important.”

Some agents — there are about 20 immobiliers in the valley — suggest that up to 80% of buyers are British. Currency dealers are also experiencing a surge in mortgage inquiries from Britons who are looking for properties in the French Alps.

“Our clients are nearly all men, single or ‘dual income no kids’, high net worth, 25–35 years old and professional,” says Andrew Hamilton, marketing manager of Baydonhill, a foreign exchange specialist. One client recently purchased a chalet in Méribel for £1.5m.

“There is a direct correlation with the high bonuses in the City this year. Most of our clients buying in the Alps work in the City, with many listing their jobs as lawyers, accountants or analysts.”

In response to this growing demand, developers are focusing on the high-end market. Gone are the days of the rabbit-hutch, sauna-style development that characterised much of the building in ski resorts in the 1980s and early 1990s. Then, new property schemes were built to be as affordable as possible, and some owners were happy to sleep in bunk beds in the hallway.

The modern alpine property, however, is becoming the mountainside equivalent of a loft apartment, boasting wide lateral spaces, state-of-the-art kitchens (for the chalet girl, of course), sleek, contemporary lines and the latest in technology. City boys, after all, want their properties equipped with WiFi and plasma screens, so they can keep up with sporting highlights back in Britain and watch their James Bond DVDs. Former hotels and barns in the valley are being converted into large flats, and instead of box rooms with bunk beds, each bedroom comes with its own en-suite. It is loft living with altitude.

Grosset Janin, a chalet designer based in nearby Annecy, has shaken off the image of dark, almost creosote-coloured chalets and builds instead in a light wood that ages naturally. “Ski chalets can look dated,” says Edouard Clavell, a sales manager at the firm, who is helping six clients — all higher up the City’s ladder — to build their own chalets.

“Two years ago, more or less every chalet had the same interior in every resort, in every price range. That is changing. Buyers are willing to pay 20% extra for branded kitchen appliances, stainless-steel kitchen tops, stone-carved sinks, plasma screens and cut-ting-edge designs in the bathroom.”

It is not just Chamonix that is catching the eye of City gents in search of an alpine investment.

“Since the bonuses started increasing three years ago, we have seen the number of City highflyers buying in the Alps grow by about 15% a year,” says Nathalie Turchet, London-based sales manager for MGM Properties, which has sold homes in the French Alps since 1960. “They are looking in Chamonix, Megãve, Val d’Isãre and, if they have a big budget, Courchevel 1850.”

There are those who can’t afford to buy in these towns, and Turchet has noticed a rash of interest in Samoëns in the Grand Massif, where clusters of alpine villages surrounded by 420km of ski runs have seen prices rise by 10% in the past year as investors, always keen to spot “the next big thing”, move in.

And at Vallorcine, a 15-minute drive from Chamonix, where Erna Low launched Les Aiguilles Rouges last month, a development of 80 flats at the foot of the cable car, more than half the flats were snapped up by “affluent London investors”. Prices in the area, one of the least developed spots in the valley, start at £165,000 and are about 50% cheaper than in Chamonix itself.

Paul McCulloch, co-founder of French Mountain Property, based in Landry, confirms that the City’s recent run of big bonuses have been behind the surge in demand for properties in the French Alps. “These buyers are all looking for a sound investment,” says McCulloch. “Some want a lifestyle bolt hole in the Alps, others are looking to maximise their investment by using the property to entertain clients, and/or by renting it out to holidaymakers.”

McCulloch believes homes in the area are viewed as sound investments because they can be accessed quickly: there are good transport links between London and Geneva and Lyons.

“Some of the dedicated ski nuts will study weather reports every day during the season,” he says. “If there’s a big dump of snow, they’ll shuffle meetings and jump on the first plane out. If all your ski gear is in your chalet, you have a season ski pass and a car permanently parked in the long-term car park at Geneva, you’ll cut your time in queues and maximise your time on the slopes.”

McCulloch adds that there is a premium to be paid for properties at a higher altitude, particularly during winters with poor snow. For that reason, too, Chamonix is an attractive proposition. The town attracts just as many visitors in the summer as well as in winter: Mont Blanc is, after all, Mont Blanc.

Mark Hepburn, 29, a sales trader at Merrill Lynch, is happily renting a flat in London but bought a two-bed chalet apartment in Chamonix for £164,000 with his brother, Iain.

“It’s an awesome place,” he says. “It has some of the best skiing in the Alps and is very accessible. If you spend a lot of time working, it is a nice place to get away from it all. It just made sense to invest there.”

Hepburn, who employs an English-speaking agent to manage his holiday lets, says the rental income from the flat is a bit like his skiing: quite “fair”, but more of a medium- to long-term project.

“I’ll always want to go skiing,” he says. “Some of the other high-altitude, purpose-built resorts are just crammed with concrete high-rises in a bowl, but Chamonix has real charm as well as some good bars.

“Munchies is a great place to go if you want to impress a girl.”

- Baydonhill, 020 7594 0555, www.baydonhill.com; French Mountain Property, 0845 324 3521, www.frenchmountainproperty.com; MGM French Properties, 020 7494 0706, www.mgmfrenchproperties.com

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