BUT as my appetizer of baked chèvre arrived, I reminded myself that even some of the top-ranking Cathar holy men, known as “pure ones” or “Perfects,” were not entirely immune to Languedoc’s less spiritual attractions. The historian René Weis records how two Cathar sages called the Authié brothers had a fondness for exotic spices, as well as fish terrines, local cheeses, honeys and “good wine.” One of their hosts, concealing the brothers in his home from the Inquisition, set up to hunt down and purge the remaining Cathars, went forth “in search of a better and more renowned wine than the one he kept in his own residence,” at considerable personal risk. This was still the Mediterranean, after all.

Today, you could never accuse the good people of Languedoc of hiding their heretic heritage. “You are in Cathar Country” proudly blares a sign on the busy highway from Avignon, followed by concrete statues of Cathar knights.

The romantic castles, superbly positioned on mountain peaks that can now be reached by car, have almost all been lovingly salvaged and adorned with lavish visitor centers, daily re-enactments of medieval life and light-and-sound shows. There is a roughly 150-mile hiking trail that links the key sites, called the Cathar Way, and another following the routes that fleeing heretics took through the backcountry.

I realized that there was more to this than just bringing in tourist euros when I saw a series of graphic novels for kids called “I Am Cathar!”

While the theological basis of their fight is alien to most of us today, the Cathars maintain a heroic aura for holding out as long as they did against overwhelming odds. For over a century after the official defeat, the survivors behaved like resistance fighters against the Inquisition, hiding out in the countryside and smuggling Cathar holy men from barn to barn. And quite apart from their underdog appeal, there is something compelling about their self-denial, which often led Cathars to choose being burned at the stake rather than renounce their faith. In the words of the French historian Emmanuel Le Roy Ladurie, Cartharism is like a dead star, which, after an eclipse of many centuries, again gives off “a cold and fascinating light ...”

My plan was to take a weeklong road trip through Languedoc toward the rugged border with Spain, to get to the heart of this medieval epic.

Unfortunately, my chances of imagining the historical drama seemed remote at my first stop, the town of Carcassonne, the famous gateway to Cathar Country, which manages to be both wildly spectacular and hopelessly cheesy. The first vision of its fairy tale fortress, La Cité, takes your breath away: Its enormous double ramparts, hovering on a hillside above the town, have 52 towers, each one crowned with fantastical “witch hat” turrets. These were actually added during Carcassonne’s restoration in the 19th-century Gothic revival, but the effect is magical  from a distance. The down side to all this splendor strikes you when you enter the imposing fortress on foot, having parked your car in the vast lot or the Ville Basse, the Lower Town, where almost all of the 45,000 inhabitants live today. Carcassonne is now one of Europe’s most popular tourist sites, and a tide of visitors is continuously pressing over the drawbridge into La Cité’s only entrance, then squeezing into the even narrower Rue Cros Mayrevieille, where rows of souvenir shops sell Lord of the Rings daggers, wooden halberds and plastic helmets, like an endless Gothic Halloween store. Still elbowing through the crowds past a torture museum and haunted house, I started to feel like I was in Duloc, the “perfect” medieval town of “Shrek.”