Castles: Monuments to a defeated heresy

Set mainly in the Corbieres region of France are 20 or so ruined castles, former bastions of the Cathars, perched high on craggy rocks. Here your breath will be taken away by the views, the settings - and the history, writes Emily Passmore.

The Corbieres region is one of the poorest in France, so you won't find it crammed with tourist shops and restaurants. But a trip is well worth while if what you want is seclusion, history, and the most romantic of settings.

The Cathars, or Albigensians, were regarded in the 12th and 13th centuries as heretics - and they had the oddest of religions, derived from Zoroastrianism. They believed that the Devil had created earth which was a kind of living hell for wrongdoers. They disregarded the Old Testament, and they refused to bow down before Christ (since, if he were on earth, he could hardly be the son of God). Their priests, known as Prefects, were completely free of sin (rather as the Clears are meant to be in Scientology); they weren't allowed to eat meat or have sex. Sexuality was considered a sin, since all it did was perpetuate the ghastly human race. Indeed, according to one historian, sexuality was seen as a "diabolical trap, a horrible, repugnant snare that closes in all living reality". (The word "bugger" is derived from the word for Bulgarian, many of whom became Cathars in the Middle Ages.) And there are connections between some of the esoteric symbols of the Cathars, and Nazism.

During the Albigensian Crusade in the 13th century, when the Roman Catholic Church waged war on the heretics in southern France, the Cathars were forced to retreat to these romantic castles; in the end, though, they were completely erased.

From the crumbling walls of Chateau d'Aguilar to the four chateaux at Latour, the castles remain in various states of ruin. Up in the clouds at the Chateau Peyrepertuse, a castle built on the very tip of a crag, surrounded by sheer rock face hundreds of metres up, it is easy to imagine how isolated, hungry and desperate the Cathars must have felt when pursued by their enemies. There remains a curious lavatory sticking out of one end of the castle; anyone scared of heights who looked down the hole would think twice about relieving himself.

Peyrepertuse is just one of the best castles and most taxing of climbs; we saw it surrounded in mist like a London pea-souper, and I was so frightened of wandering to the edge and falling off that I remained rooted to the spot until my companion appeared out of the clouds and rescued me. The only trip to beat Peyrepertuse is Latours. Although some areas here are roped off, there are many unguarded strips where you feel it would be all too easy to fall down into the hands of the waiting Crusaders below. Montsegur is demanding, but well worth it, if you're not put off by passing the field where 450 Cathars were put to death at the stake. Four Cathars escaped from Montsegur with, it's said, a mass of Christian treasure, and rumours have since abounded that identify this treasure with the Holy Grail.

If, before you go, you can read Montaillou, written by the French historian Emile Le Roy Ladurie, which was based on Inquisition records of around 1300, you will get a much better idea of what life was like during the period. It's a bit like a medieval soap opera, and tells you who was sleeping with whom, who was guarding whose sheep, what the corrupt parish priest has to say about the yellow crosses the Cathars were forced to wear, and so on.

Montaillou itself is one of the prettiest of the castles, the most easily accessible and, surprisingly, the least tourist-ridden. Standing inside its ivy-covered walls, listening to the bells of the cows below mingling with the church bells, and overlooking miles of undulating hills, you feel as though you are right back in the 13th century.

The area attracts its fair share of New Agers, since the castles are all situated around the mysterious Rennes le Chateau, where in the 19th century, a Father Sauniere uncovered a mass of mysterious manuscripts and esoteric material, left, it's said, by the Knights of the Round Table. He became suddenly so incredibly rich that he was able to refurbish the church completely (unfortunately he had no taste; it's a terrible painted interior full of naff statues), build himself a mysterious tower and formal garden, and rebuild the walls around the town. His great wealth was so inexplicable that he was excommunicated for his luxurious lifestyle. Perhaps it was he who discovered the Grail itself ...

Carcassonne is a good place from which to start off, a medieval town completely restored by Viollet le Duc in the 19th century; but it's too perfect, and tourists jostle cheek by jowl as they visit shops selling scented candles, Provencal duvet-covers and overpriced pottery.

Instead, I'd advise booking at the Hotel Costes in Montsegur - simple and basic, but very clean. It's one of those typical, family-run hotel- restaurants found all over France, with delicious plats du jour, roaring fires, two dogs, and local wine. Ideal after a long slog up to a chateau and back.

Getting there: Rail Europe (0990 300003) has a service from London Waterloo to Carcassonne via Paris and Bordeaux for pounds 142, taking 11 hours.

Staying there: the Hotel Costes in Montsegur is on 00 33 561 01 10 24. A double room costs 220F (about pounds 24) per night.

Further information: French Government Tourist Office, 178 Piccadilly, London W1V 0AL (0891 244123, premium rate); fax 0171-493 6594).