In the Spanish mountains where Hemingway found the hero for his great war novel, monks gave birth to a wine now making a big impression. Clive Irving follows the trail down to the sea

First, there was the story about the traveling order of Carthusian monks. Sometime in the twelfth century, they ran into a shepherd up in the mountains who said that he had had a vision. He'd seen angels rising, as though following a stairway up the rock face to the heavens. The traveling order then stopped traveling and set up a monastery on the spot.

Second, there was the food market. Such a food market that the term hardly does justice to the impact on the senses.

Finally, there were the cats. A procession of them, advancing with measured steps toward their appointed place. Advancing, let it be said, without catlike impulse, one by one in a perfect line. No stalking, no hustling.

I reflected on where this chain of events had taken me as I sat in the shade of a bamboo awning, drinking a cold Catalonian beer. Budgerigars were chirping in a tin-roofed cage near my table, the tin amplifying their confinement. I felt like chirping too—not in defiance of confinement but with the contentment of having discovered a part of Spain unlike any I had ever seen. Thanks to those monks, that market, and those cats.

The terrace, together with a small bar and restaurant, sat on a concrete pontoon that seemed to be floating amid acre after acre of rice fields, which stretched away until the intense green bled into a pearly haze of heat. Several men were working, bareheaded and up to their calves in water, picking at weeds. A lone egret was pecking amid the rice.

Scarlet bougainvillea hung from the white plaster walls, petunias spilled from terra-cotta pots. It seemed an aberrant palette for southern Catalonia, a region of mesas and wide, dry riverbeds, of mountains where flecks of mica reflected sun from rocks with the sharpness of city lights. But here in the delta, some 120 miles southwest of Barcelona, it was another world.

The Ebro is the longest river in Spain and the only one of the country's major rivers to empty into the Mediterranean. It rises near the Atlantic, in Cantabria, runs through La Rioja, Navarra, and Aragon, and, having come 565 miles, finally flows through its own massive silt deposits to the sea. On a map, the resulting wetlands can be seen to follow the shape of a great alluvial fan extending outward from the coastline for miles on each side of the river's channel.

And in a way, that has been the salvation of the delta. This is, after all, the coastline that gave a bad reputation to the term costa. In the days when the Spanish Mediterranean coast was a bargain-basement destination for the boozy sunseekers of Britain and Germany, many quiet fishing ports on the Costa Brava and the Costa del Sol became concrete jungles. Luckily, the Ebro Delta was bypassed by the costa machine. It lay to the east, undisturbed and largely out of sight of the buses and cars speeding south, one of geography's artful sanctuaries.

But I must return to those Carthusian monks. It's a good bet that wherever monks have put down their roots there will be something worth drinking: Over the course of centuries, they have given us Champagne, Chartreuse, numerous brandies and liqueurs, and great beers—so many, in fact, that monkdom sometimes seems to be one long binge.