French dressing: Lyon's gastronomic larder

From the reeds we catch our prey's pulse-quickening plop. "Voilà," Jean-Paul whispers. The tension is electric. With surgical precision his wand-like rod is probing far along the bank, the tiny ball of stocking he uses for bait fluttering like a butterfly among the lily pads. The mist is radiant with sunshine. A flight of mallard skitters down. It is another of those Dombes dewy-fresh mornings when the world really seems to be restarting from scratch.

The lovely watery triangle between Lyon, Bourg-en-Bresse and fairy-tale Pérouges is billed as the Land of 1,200 Lakes. Created by 12th-century monks for farming fast-day fish, the lakes are drained periodically to harvest the carp and corn is then grown on the fertile dry beds until refilling with rain completes the cycle. Remarkably, after 800 years the eco-friendly system still flourishes, preserving one of Europe's most important wetlands.

Another heart-lurching plop. Jean-Paul scarcely breathes. Then suddenly he strikes - a bright emerald flash soaring three metres and skydiving neatly into his sack. "Got it!" A piscatorial tour de force, and his grin is exultant. "Formidable, Monsieur!" He winks and licks his lips. It is a perfect day too for edible green frogs.

Emblematically Gallic, the prized amphibious by-product of so many lakes is ever more elusive. Commercial frogging has been banned in the EU and most specimens dissected in restaurants today have hopped from foreign parts. Even here for authentic Dombes frog suppers you must first catch your own - or splash out at three-star restaurants at whose back doors, some allege, schoolboys fence their catch at €60 per kilo.

The Dombes twitters like an ornithologist's dream. Jean-Paul is also a naturalist, proud that 400 species rate as frequent flyers, yet in his champion frogger's hat he sounds wistfully ambivalent about climate-change immigrants whose partialities for frogs gravely diminish those that sizzle in his pan.

Near Villars-les-Dombes - one of those tiny French towns you either drive through without noticing or buy a house in and stay - Jean-Paul helped to hatch a world-class attraction. The vast Parc des Oiseaux - Europe's biggest bird park fused to the Dombes nature reserve - lures 250,000 ticket-buying visitors annually plus a million or so feathered freeloaders. Divided into continents, its giant landscaped aviaries offer encounters with some of the planet's rarest birds. There are African savannahs, Chilean volcanoes, tropical jungles and Antarctic wastes.

Its slogan "Birds without frontiers" takes wing where reserve and park adjoin: here the flashy first-class residents are regularly mugged by 30,000 wildfowl. Although the lakeside restaurants do not serve frogs, during lunch two cocky whoppers croak boldly from the bank.

We spend a lake-encircled night at the Hotel du Gouverneur. The modernised chateau is now a golf resort whose three 18-hole courses weave among the lakes, promising golfers "a naturalist's paradise". Here golf's avian vernacular at last becomes explicable: with birdies by the thousand even novices can score a heron or swan. Wild boars on fairways are director Ugo Joubert's literal bêtes noires, for ever grubbing up his greens. Equipped with niblick and binoculars, a round is like a nature ramble.

Lunch is unforgettable. Top chef Ludovic Colomb sautés Jean-Paul's morning haul. Golden and crisp, tasting vaguely like chicken, they are delicious. Connoisseurs, he confides, munch the bones too, but he cautions mere beginners.

The region is Lyon's gastronomic larder. Besides fish and frogs, its glories include incomparable Bresse poultry. Exploring twisty lanes we find villages such as Bouligneux whose 300 inhabitants can ingest expensive calories at three gourmet restaurants, two with Michelin stars. Amazingly no one appears overweight. The lake-sequined meadows patrolled by herons and storks look as if they come from a children's picture book.

The only sizeable city in the area is Bourg-en-Bresse, a bustling regional hub renowned for good restaurants. Bourg's jewel is the gothic church and monastery of Brou, a monumental paean to imperishable love as extravagantly sumptuous as the Taj Mahal. It was begun in 1506 by emperor's daughter Margaret of Austria as a sepulchral shine for her young husband Philibert the Handsome; craftsmen imported from Europe's four corners spent 25 years on its no-expense-spared eulogy in stone. Bathed in day-long golden light, their side-by-side marble effigies - she surviving him by three decades - touchingly resemble a middle-aged mother and adolescent son. The grandiose adjoining monastery with three double-tiered cloisters was home to just 12 monks recruited to pray for the adoring couple's souls. The exquisite building is now Bourg's art museum.

The Dombes boasts a truly show-stopping finale, a pocket-sized but perfect medieval city: magical Pérouges. On its crag above the morning mist, turrets glowing in the sunshine, it looks like a dreamscape. Inside the walls you find the Middle Ages frozen in time.

Legend has it that Pérouges was founded by Gauls fleeing home from Perugia, after their Italian colony was stormed by the Romans around 300BC. The two hilltop sites are strikingly alike. Until recently they shared a 2,000-year-old patois. When the Romans caught up three centuries later, Pérouges gave Caesar a ready-made fort. Later came Burgundians, later Savoyards. It withstood its first recorded siege in 1167. Outside the portcullis, again vainly besieged in 1468, an inscription in Pérougian crows: "Pérouges of the Pérougians - impregnable city - the Dauphiné scoundrels tried but failed to take her!" You got into Pérouges only when they opened the gate.

After centuries of prosperity, by 1909 its population had dwindled to nine aged souls. Laws were enacted to have everything razed. But then Pérouges-born professor Anthelme Thibaut, inspired by the city's patron Saint George, began a battle to save it beneath a banner as defiant as the inscription on the gate: Pérouges that had withstood every assault would only fall over the bodies of the people who loved it. Happily they won.

Today the Thibaut family hosts the historic Ostellerie du Vieux-Pérouges - possibly France's most atmospheric hotel - which first opened for business in 1432. The medieval splendour makes even anarchist republicans feel baronial. Our oak-panelled room was full of antiques. We could have parked our car in the chimney it was so wide.

Beneath the famous lime tree by the Ostellerie, planted in 1789 to mark the Revolution, Bill and Hillary Clinton addressed the citizens before tucking into the hotel's renowned cuisine. Whether either chose frogs is not recorded; it's unlikely that they, like us, ever shared a better meal.

In the 15th-century dining room, after foie gras escalopes, roast Bresse chicken and Dombes carp in mustard sauce, our capacities were tested by the traditional dessert, galettes de Pérouges, a sort of crème brûlée pizza.

There are still only 70 citizens within the walls making sure that Pérouges remains a real community. The house façades are maintained publicly but other repair costs mean that many stand empty. At weekends tourists throng from Lyon but after dinner we find the dark alleys deserted.

Next morning we join them harvesting the fish. The men at the lake are as taciturn as monks. Five wade stealthily into the reeds to the circular net; with infinite caution raise its submerged rim. It is a biblical scene; how men once fished in Galilee; how men have fished here for 800 years.

The net was laid last night. Carp, unsuspecting, have congregated over it. Silently, in unison, the men abruptly heave. The tranquillity explodes: everyone is shouting, maelstroms of white water, seething silver scales. Other men plunge in to corral the threshing fish. Basketfuls are lugged ashore and suddenly it is over. Six hundred kilos of carp landed in 10 minutes. Some fishermen are whistling. In the restaurants of the Dombes they will be frying tonight.

TRAVELLER'S GUIDE

GETTING THERE

Rail Europe (08707 371371; www.raileurope.co.uk) offers routes to Lyon via Paris. Lyon is also served by British Airways (0870 850 9850; www.ba.com). Ryanair (0871 246 0000; www.ryanair.com) flies to Grenoble. To reduce the environmental impact, you can buy an "offset" from Climate Care (01865 207000; www.climatecare.org).

STAYING THERE

Hotel du Gouverneur, Monthieux (00 33 4 72 26 42 00; www.golfgouverneur.fr). Doubles from €90 (£64). Ostellerie du Vieux-Pérouges (00 33 4 74 61 00 88; www.ostellerie.com). Doubles start at €195 (£139).

VISITING THERE

Parc des Oiseaux, Near Villars-les-Dombes (00 33 4 74 98 05 54; www.parcdesoiseaux.com). Opens daily 10am to dusk; admission €12 (£8.60).

MORE INFORMATION

Ain Tourism: 00 33 4 74 32 31 30; www.ain-tourisme.com.

Villars-les-Dombes: 00 33 4 74 98 06 29; www.villars-les-dombes. com.

French Tourist Office: 09068 244123, 60p/min; www.franceguide.com.