Rioja, of course, is not the only wine region with requirements for minimal aging. Montalcino, for one, requires brunellos to be aged four years before they can be released, five for brunello riservas. Yet even when brunellos are released, they generally need years of additional aging before they are really enjoyable.

Rioja is different. The old tradition was for producers to age the wines until they were ready to drink, well beyond the minimal requirements. Only a few wineries still offer this service. But judging from our tasting, the difference is clear. Our top four bottles were all well-aged reservas from producers who continue to perform this traditional practice.

No. 1 was the 2001 La Rioja Alta Viña Ardanza, a wine that right now is absolutely delicious, but is also so much more than that. With lightly spicy fruit flavors, mellowed by long aging in barrels of older American oak, it was a brilliant example of a classic Rioja, with complexity and finesse. The 2001 vintage is widely regarded as great, and the producer, La Rioja Alta, thought so highly of this wine that it called it Reserva Especial, only the third time one of its wines has earned that designation, along with 1964 and 1973.

Our No. 2 bottle was also a 2001, the Reserva Señorío de P. Peciña from Hermanos Peciña, a tangy, pure wine that offered more fruit power than the Viña Ardanza, if not so much complexity.

The next two bottles were both from R. López de Heredia, the great bastion of traditionally made Rioja. One, the 2001 Viña Tondonia, our No. 4 bottle, was still youthful. Its straightforward fruit flavors have years of evolution left. Right now, the wine is earthy and mellow if not yet exceedingly complex.

By contrast our No. 3 bottle, the Viña Bosconia, was from the 2003 vintage, an odd year marked by excessive heat across Europe. This wine shows no obvious sign of the vintage, though. It’s exceedingly delicate, which is unusual for a Bosconia, and lovely right now, but is unlikely to age as long as the Tondonia.

The remainder of our top 10 were all younger, two bottles each from ’04, ’05 and ’07, and these bottles were illuminating.