Long before Madrid was the capital, or really much of anything, the Calle Alcalá--now one of the main boulevards of the city--was one of these transhumant routes. In 1418 the City of Madrid signed an agreement with the Good Men of the Shepherds' Mesta, a powerful syndicate of landowners and ranchers, allowing the flocks to pass through the center of the city. Paintings from the 17th and 18th centuries show the city transformed when the flocks came through: the streets filled with refreshment stands, dances and brothels to serve the passing shepherds, who came loaded with dough from selling their wool.
Until well into the 20th century, some flocks still used the boulevard in their annual migrations, but by mid-century they had given up. Then in 1996 an organization defending pastoralists' rights appealed to the 1418 law, and demanded their right to cross through the city, now as a demonstration more than as a migration. Thus the Fiesta de la Transhumancia was initiated, and has continued since then.
It's an odd event. Pastoralists come in their traditional get-ups from several provinces of the country, often accompanied by folkloric dancers and musicians. The whole thing looks disconcertingly like the Pueblos de España parades encouraged by Franco. But the motivation is different: this is not about national unity. This is about conserving what is left of the social and natural ecosystems which depend upon transhumance.
The organizers are a motley crew, including shepherds, ecologists, ethnographers, horse enthusiasts, and hikers. They don't go in for pamphlets or banners, so most of the spectators don't really know why they're there (except that its cool to see sheep in the city), but their arguments include: the preservation of the cañadas as a public resource for hikers and cyclists as well as for transhumant livestock; the sustainability and quality of this livestock (conservation of old breeds, healthy natural feed, etc.); the preservation of traditional rural ways of life; and the recuperation of meadow ecology.
This last point was one I hadn't thought about before, and found interesting. While anyone who has driven through the vast expanses of grazing land in Spain may think that this is a very uniform, simple landscape (grass, live oak and cork trees, more grass), these pastures are in fact incredibly diverse ecosystems, with thousands of types of plants and small animals inhabiting them. But it seems the biodiversity of your average meadow in Spain is plummeting. Why? Because the livestock no longer migrate, and the plants never get a chance to live out their whole cycle because they are eaten and trammeled before they can seed.
Jesús Garzón, a renowned Spanish ecologist and conservationist, has recently shifted his activities from the defense of large endangered species like the Iberian linx to the defense of transhumant pastoralism. He claims that all the very different ecosystems of the Iberian peninsula have been connected since the Ice Age by migrations from the high northern pastures to the warmer southern ones, and that over the millennia all have come to depend upon this movement to maintain their equilibrium and breadth of genome. The transhumance, therefore, is not only a sustainable way of raising livestock but also an essential element of the natural cycle itself: the millions of seeds which cling to a woolly sheep are crucial for maintaining healthy plant populations.
So the street should be mobbed with concerned citizens, shouting "long live nomadic pastoralism!", right? Alas, no. The crowd is composed mostly of surprised tourists, delighted kids, and a lot of elderly people originally from small villages who come once a year just to catch sight of the sheep, just to get a whiff of that other, rural world that feels so far away.