“We’d often been to France on holiday, but we’d always got off the ferry and straight on the motorway heading south,” says Uma, 35, an IT project manager. “We’d never visited the north.”

But on their first househunting trip they found a two-bedroom farmhouse in Campagne-les-Hesdin, a pretty village 30 miles from Boulogne and 25 minutes from Le Touquet. They remortgaged their £750,000 home in Cuffley, near Potters Bar, and paid £102,000 cash for the cottage in March. They now let it for £350 a week in high season.

With two small sons, Aaron, 2, and Adam, 6 months, journey times were crucial. “We wanted somewhere we could go in the car without the children getting distressed,” says Uma. “We’ve done the trip in two and a half hours, but we were driving fast.”

Until the late 19th century, the Opal coast, as the region around Le Touquet and north of it is known, was little more than sand, sea and pine forests. Then artists began to flock to the area to paint its magical light. They were followed in the Edwardian era by English aristocrats, attracted by the healing air that was said to cure a string of ailments. In the 1930s, Le Touquet’s elegant hotels and casinos became popular with British gamblers including the Prince of Wales — playing games banned at home.

The Opal coast’s 19 golf courses are now among its biggest attractions. “About 65% of my visitors are English,” says Ken Strachan, general manager of Les Pins, which celebrates its centenary next year, and Les Dunes courses near Hardelot. “I am aiming to make Le Pins the best in Europe.”

The region has plenty of other attractions: its miles of white sandy beaches are ideal for sunbathing, horse riding, sailing, surfing and land yachting, a hugely popular sport locally in which racers tear along the sand at breakneck speed in a cross between a yacht and a go-kart.

After several weekend visits redecorating their cottage, the Mays family has just spent its first proper holiday there. “Le Touquet has a beautiful beach and we spent whole days there,” says Uma. “There’s an amusement park that Aaron loves.”

Nearby are acres of forests, beautiful river valleys, nearly 30 miles of horse-riding trails, excellent tennis centres, fine food and wine — and properties that are, by English standards, still relatively inexpensive.

“The property market has been squeezed from both ends,” says Pierre Vankeirsbilck of Agence Côte d’Opale, an estate agency in Le Touquet. “Prices in this area have more than doubled in the past three years. Elsewhere in provincial France they’ve gone up by only 30%.”

Penny Zoldan set up Latitudes, a London-based agency that helps British buyers find property in northern France, in 1989. “When I started you could buy a small cottage in the country for between £10,000 and £20,000, which was the price of a studio in Le Touquet,” she says. “But what was £30,000 then is now £100,000.”

The Channel tunnel and the new A16 motorway that can get you from the coast to Paris in under three hours have fuelled demand in the area. A shortage of space is also pushing prices higher.

“Le Touquet has no more land,” says Zoldan. “They are building out to Etaples and calling it Le Touquet. In the end, Hardelot and Le Touquet will join up.”

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