EIGHTEEN months ago, a shepherd rode into the Puerta del Sol with a stout stick in one hand and a mobile phone in the other. Madrid's central plaza came to a most untypical standstill as the citizens gawped at a sight that would have been commonplace 50 years ago 2,000 Merino sheep trotting smartly through the capital, accompanied by horsemen, mastiffs, pigs and goats.
Cesareo Rey Rey, a veteran shepherd, and his colleagues in the Proyecto 2,001 were reasserting a practice which may be nearly as old as humanity, and had almost disappeared.
The transhumancia, a great annual migration of animals and people up and down the Iberian peninsula, probably started when the last Ice Age began to retreat northwards. Great flocks of game moved up to the high sierras of the north in late spring, when the southern pastures became intolerably hot. They came back when autumn snows made the mountains inhospitable. Human beings, still hunter-gatherers, moved with the wild herds.
As pastoral society developed, cowherds and shepherds followed the same pattern with domesticated livestock. Eventually, the richest of them formed the Mesta (shepherds' council), one of the most powerful monopolies in Spanish society until the beginning of the last century. The Mesta fiercely defended a 124,000 kilometre network of broad rights-of-way known as canadas reales - royal drovers tracks - many of which went straight through big cities, hence Cesareo Rey's dramatic appearance in Madrid. The transhumancia left indelible marks on the Spanish landscape, physical and cultural.
The people in Proyecto 2,001 don't stress this, but the Mesta had its opponents. Like the farmer and the cowman in the musical Oklahoma, crop-growers and migrants could not easily be friends. The former understandably resented having to leave scarce arable land permanently fallow for a twice-yearly pastoral caravan.
The Mesta usually got its way, however. and it was trains, not settled farmers, which sent the old transhumancia into decline. By the 1950s, most sheep and shepherds were travelling to new pastures by rail. Illegal developments encroached on the disused canadas. An ancient tradition seemed to have died.
Forty years later, enter Jesus Garzon, already a legend in Spanish ecology. If you think all Greens are vegetarian wets, you need to meet Garzon. He eats (very) red meat with relish, and traces the magic" ritual of bullfighting from its agricultural origins without passing any moral judgements. He wouldn't appeal to the politically correct in the animal rights movement, but his record speaks for itself. In the 1970s, he fought to preserve the unique environment of Monlrague in Extremadura, home to rare birds including Black Vultures and Black Storks, from the menace of eucalyptus farming. Today the area is specially protected, and these species are increasing. Some people credit him with single-handedly saving the Imperial Eagle, one of the glories of European wildlife. He brushes off the compliment: "It was a matter of explaining to farmers that they should not strip cork from oaks where the eagles were nesting. Now they wait a month or two, the chicks fly off, and the farmer still gets the cork."
PROYECTO 2,001, of which he is president, is imbued with a similarly practical spirit. Set up by the European Natural Heritage Fund, but now largely autonomous and drawing two million Ecus from the EC LIFE programme, its primary aim is to re-establish the transhumancia. While some EC experts have described the project as "the most important European act of conservation in the 1990s, others have difficulty in recognising the environmental virtues of a programme based on agricultural commerce.
Since 1993 livestock have again travelled four of the 10 great trails on foot. A 1995 law actively reasserts the old rights-of-way. One of the first things Garzon did was to use economic studies to show that the revival would create stable rural employment for young people. The countryside, without its people, means little to his school of ecology.
A second key element is the restocking of the genetic pool of sturdy, indigenous strains of cattle, sheep, horses and fowl suited for the transhumancia, and threatened with extinction by breeds imported for mass production.
Just before this year's transhumancia began, Garzon took me to a fairytale, flowery meadow just below the current snowline in the Cantabrian Picos de Europa. Seven affectionate little Asturcon horses, two docile Tudanca bulls and a Pedresa cock, plus harem, form one nucleus of the project. Then he went down to another valley and did a deal with a canny old farmer for 50 head of Tudanca cows, making the Proyecto herd the largest in existence. Such an endeavour seems much less quixotic in the light of mad cow disease.
The third aim of Proyecto 2,001 is the improvement of the quality of life for people living along the trails. A whole culture of craftwork and celebration has been lost with the transhumancia, which brought seasonal visitors to countless villages. Perhaps the most surprising skill the shepherds exercised was a remarkable piece of sublimated eroticism they used to knit woollen stockings for their girlfriends, complete with an embroidered dedication in verse along the thigh.
Judiciously managed ecotourism along the trails forms part of the project, which also offers a unique method of fostering and linking many threatened wildlife habitats. Wild fellow travellers are already putting in appearances, a first glimpse of Garzon's dream of reviving an entire ecosystem.
The mastiffs which protect the sheep now have to wear fearsome iron collars with three-inch spikes just long enough to dissuade wolves, which are attacking the herds in increasing numbers, from trying to tear out the dogs' throats. Both the wolves and the mobile phones distinguish this sort of endeavour from the sort of pastoral idyll Wordsworth wrote about. But, in the relentlessly "modernising" Spain of the 1990s, does it really stand a chance of working?
The scheme seemed to get a major boost in early June, when Spain's first minister for environment, Isabel Tocino, paid a highly publicised visit to this year's flock. Front page photographs in several papers showed Ms Tocino, a formidable figure in Spain's new conservative government, dressed as a shepherdess and doing folk dances.
She said that the revival of the transhumancia "counted with her full support". Two weeks later, she again made the front pages, this time exhibiting the same formidable figure in motor cycle leathers at a bikers' rally. A cynic might conclude that she has more interest in self-promotion than in ecology.
Things seemed to be coming badly unstuck two weeks later, when we tried to intercept the flock, as arranged, in the Castillian cathedral city of Palencia. Honeyed evening sunlight. spilling over an ancient bridge leading into the city provide an almost-too-perfect setting for the arrival of a medieval agricultural phenomenon.
But the sheep never arrived. One shepherd was stubbornly holding his animals in the hills above the city, having suddenly become worried about the risks of the traditional route.
After waiting a couple of hours, a gaggle of waiting journalists dispersed. Jesus, Garzon finally drove myself and Ricardo Cristohal, an artist and newspaper illustrator, up to the flock. Once again, the setting was idyllic. Thousands of sheep were ambling into a hazy sunset, the air heavy with wild thyme, mint and camomile crushed bye their passage, and rinsed with the liquid sound of their cencerros (sheep-bells).
However, the human atmosphere jarred sharply with this pastoral vision. None of the shepherds returned our greetings, and one of them shouted rudely at us to get out of the way.
Somewhat apprehensive we caught up with them again the next morning the sheep flowing down a lane in the daylight like a "river of wool" as Garzon put it, before he left for Cantabria. For the next 12 hours we followed them at an easy pace. The canada was (mostly) remarkably well preserved, a 60-yard swathe of fallow land running through farms and blights of bungalows. We had to cross a main road several times, so the flock enjoyed the officially-provided services of three shifts of good-humoured Guardias Civiles. They gave us total priority over traffic, and were not above using their batons to stop the odd ewe making a break for some unknown border.
If the police were enjoying themselves, however, the shepherds were not happy campers. In countless visits to the very hospitable Spanish countryside, Ricardo and I agreed, neither of us had ever encountered such a sullen and hostile response, all the odder since we were invited guests, the only ones for the day. One young lad did his best to give us what little practical help we needed, but the three older men made it abundantly clear that they had no interest in sharing the lore of the transhumancia with us. Several citizens, who had driven out to see the flock pass by, received similarly dusty welcomes.
PERHAPS the shepherds had been antagonised by the media circus around the minister, and maybe they were beginning to feel like rural clowns trotted out for the amusement of city folk. Whatever the reason, in the absence of the charismatic Cesareo Rey Rey this year, they made poor ambassadors for the view that the transhumancia would improve the quality of rural social life.
In the late afternoon, we crossed the Castille canal, a marvel of masonry locks and sluices which Proyecto 2,001 is also refurbishing. Away from the road now, we followed a languid brown river, and then, green reedbeds patrolled by flamboyant golden-brown birds of prey (marsh harriers, I think), and exotically purple herons.
As night fell, we moved through beech woods into wheatfields, where an enormous farmhouse boasted a most unlikely art nouveau gate, and a strange statue of an idealised peasant woman brandishing a sickle.
Cranky shepherds notwithstanding, it had been a truly magical day's walking, set at a steady but undemanding pace by the flock. The canadas certainly offer a marvellous, ready-made route for anyone who wants to explore little known parts of the hugely varied Spanish countryside. They could, if sensitively developed and promoted, provide attractive secular alternatives to the Camino de Santiago, which has become a very popular international walking pilgrimage.
Only time will tell whether the transhumancia itself can really be revived in anything more than a testimonial manner. Its resuscitation needs serious money. EC funds and German ecological investment are drying up. Much will depend on whether the new minister really sees the idea as more than a fleeting photo opportunity.