Old vines, new gambles

Of course, Bierzo could be bigger. Priorat has perhaps 1,000 acres of very old vines, but Bierzo is home to more than 10,000 acres of heritage vineyards. Yet not all vineyards are the same, Palacios is quick to point out. Just 10% of Bierzo's vineyards are planted in the flaky slate soils -- situated on an outcropping of a subterranean geological vein that extends across northern Spain from Priorat -- that Palacios prefers. Those soils are concentrated around the Corullon area, which includes medieval Hornija.

Starting with his first vintage in 1999, Palacios' wines expressed the minerality common to wines from slate soil regions. The fresh blueberry and herbal aromas and flavors evident from the beginning have grown more intense as he's developed more single-site Mencia wines.

It could be that single-vineyard Mencia wines will be the best expression of Bierzo's potential, says Mario Rico, one of the founders of Dominio de Tares, a large vintner by Bierzo standards whose first vintage was 2000. But Spain is a country that has always relied on blending grapes from across a region. There are 9,000 vineyard owners in Bierzo and most own only one to two acres of vines, he says. Blending is the only way he can pull together enough fruit to make his wines, which are among the best selling in the United States, in part because of their reasonable price-quality ratio.

And, Rico says, slate soils may not be the only soils that produce the grapes to make a complex wine. The work of learning the effect of the various slate and composite clay soils is just beginning. "We vinify our wines plot by plot as we try to learn the terroir of the region. We still don't know much."

Still in its infancy

With less than a decade of releases behind it, modern Bierzo winemaking is in its infancy. Although dozens of Mencias are now available in world markets, the original standard-bearer, Palacios, is still the only recognized prestige producer. Whether the region has the wealth of prize vineyards necessary to provide the raw material to support an artisan wine community on par with Priorat is yet to be seen. In the meantime, wine lovers can taste the region's evolving character with each new vintage.