It is 9.30 on a mid-November morning. Not, perhaps, the ideal moment for a visit to the beach, even a beach in the South of France. Yet here we are, the photographer, Barrie, and I, making our way along the expanse of fine sand that stretches away eastwards from the substantial village of Les Saintes-Maries-de-la-Mer, the capital of the water-bound realm of herons and flamingos, black bulls and white horses that is the Camargue.

Two days ago, we flew into Arles on a foul night of sheeting rain. Now the sun shines fiercely above us in a wild, blue sky washed clear by the storm. To our right, the little waves curl placidly at the shoreline and all around us is a mass of white horses and their riders, trotting, walking, cantering, curvetting, all moving towards a single destination: the starting-point of the abrivado, due to begin at the far end of the beach at about 11am.

The abrivado is one of those curious institutions that grow up in places where men and horses live and work together: part parade, part game, part mounted party — a tradition sprung from the ancient Camarguais tradition of ranching semi-wild bulls and horses over the unenclosed marshland and scrub of the region. During the long abrivado season from early autumn to late spring the guardians, as the cattle-ranchers are known, round up selected bulls and escort them to bullfights in the arenas of the villages with which the Camargue is sparsely scattered. This weekend in Les Saintes-Maries is the climax of the season — a four-day festival attended by horse and cattle ranchers from the entire region.

The atmosphere is festive. The high-octane tension and beady competitiveness of large horsey gatherings in Britain is notably absent. There are no crowd barriers, no police, no stewards yelling into walkie-talkies. Just the sky, the sand, the sea — and wave upon wave of sturdy, trotting white horses. Suddenly the tidal flow changes direction. Groups of horsemen, each with two or three bulls embedded at its centre, move towards us at a brisk trot, like the beginnings of a cavalry charge, each group so tightly packed that you can only make out the bulls by crouching and looking for the black legs among the trotting grey. As they move down the beach towards the arena in the centre of the village, men on foot try to distract the horses and allow the bulls to escape.

Another group sets off, then another and another, and all the route is lined with yet more horses, hundreds of them, the mass of white undulating like the waves of the sea behind us. We walk back along the beach, keeping pace with the horses until we reach the village, where the roads are busy with horse-boxes and the restaurants loud with celebrating guardians, putting away huge plates of aioli and carafes of rosé, luxuriating in the sunshine, the festival atmosphere and the company of friends.

The glorious conviviality of the abrivado at Les Saintes-Maries is the mirror image of the Camargue’s other great attraction, its wild and beautiful emptiness. Sparsely populated by humans, the reed-beds, marshes, water-meadows and scrub remain the lonely realm of animals semi-domesticated and wild, of bulls and horses, but also of egrets, herons, bittern and flamingo, flocks of which administer a shock of strangeness as you spot their sugar-pink geometry of swooping curves and languid angles.

The best way to explore the secret life of this mysterious terrain is to be out in it, on foot, perhaps taking one of the guided walks offered in the Marais du Vigueirat, a conservation area of reed-bed and marsh just east of the Camargue proper, exploring by bicycle or in traditional fashion, on horseback. Almost any countryside, and especially a marshy flatland such as the Camargue, looks better from the back of a horse, as we found on a visit to Le Mas de Peint, a working cattle and horse ranch with a country house hotel at its centre, owned and un by the Bon family — Jacques, a figure of raffish elegance with a snow-white moustache and braid-trimmed velvet jacket, his architect wife, Lucille, and their son, Frederick. The hotel was converted by the Bon family from a 17th-century barn and pigeon-house of pale gold stone, built around three sides of a courtyard.

Stepping into the stone-flagged hall is like wandering into someone’s private house — smells of beeswax and wood smoke, graceful arrangements of antique furniture and everywhere, from the table-cloths to the white linen sheets, the Bon cattle brand, a B surmounted by a cross.

In the stable block, Frederick and another guardian were waiting with a trio of tough little grey geldings. In past centuries, the Camargue horses ran semi-wild for much of the year, rounded up annually for inspection, branding and gelding. In the modern Camargue, many lead a more domestic life, working as riding-horses for tourists. The breed is of ancient origin, compact and stocky with a large, square head that hints at its primitive ancestry.

Firmly lodged in Jacques Bon’s deep herdsman’s saddles, we jumped a small ditch and found ourselves in a marshland full of black cattle with long, cave-painting horns. Frederick and his fellow guardian vanished to round up some stragglers, leaving me surrounded by a thicket of pointed horns and foghorn bellows, though the ferocious aspect of the cattle belies a phlegmatic nature — at any rate, they seemed inclined to ignore us.

“The Camargue,” wrote the Provençal author Jean Giono, “conceals its mystery behind its very revelation.” Poised on horseback between the sky and the land, surrounded by the elemental sights and sounds of the semi-tamed wilderness, you feel like a witness to something rare: a harsh, primeval beauty, softened and made palatable by the tourist ranches, the comfortable hotels and restaurants, but still there, still a mystery in this ambiguous terrain, neither land nor water, that is the Camargue.

Need to know

Getting there: Jane Shilling travelled from Stansted to Montpellier with Ryanair (0871 2460000, www.ryanair.com). Return fares from £31. Car rental with Europcar (www.europcar. fr) from Montpellier airport starts at £166 a week.

Where to stay: Hotel le Mas de Peint, Arles (00 33 4 90 97 20 62, www.masdepeint.com), doubles £138. Hotel Mangio Fango, Les Saintes- Maries-de-la-Mer (90 97 80 56, www.hotelmangio fango.com), doubles £44.

Information: www.marais-vigueirat.reserves-naturelles.org. French Tourist Board (0906 8244123, www.franceguide.com)

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