The two regions are in northern Spain and are north of the capital, Madrid, which has been compared to the center point of the face on a clock. With that analogy in mind, Ribera del Duero is directly above Madrid, heading towards 12:00, while Rioja is to the northeast, between 1:00 and 2:00. The two regions are about three hours apart from one another by car and neither is coastal, though Rioja is closer to the North Atlantic, known locally as the Cantabrian Sea.

Rioja became Spain’s first Denominacion de Origen (DO) in 1925. It was also the country’s first Denominacion de Origen Calificada (DOCa), a distinction earned in 1991.

A relatively large region, Rioja spans three provinces in the Ebro River Valley and has three subregions, Rioja Alavesa, Rioja Alta and Rioja Oriental.

Wine has been made in Rioja since Roman times, and it is believed that barrel aging was introduced in the 1780s. In the 1850s, as phylloxera ravaged the vineyards of France, winemakers from Bordeaux moved to Rioja and began plying their trade, ushering in the region’s modern era of winemaking.

Ribera del Duero sits on a mesa, or high mountain plain, with altitudes between 2,300 and almost 3,600 feet above sea level. Strong day-to-night temperature shifts help preserve the grapes’ acidity, adding to its freshness and ageability.

Winemaking in Ribera del Duero dates to the Roman era as well. Benedictine monks from Burgundy were active in viticulture and winemaking in the 12th century.

Wines from Rioja labeled Tempranillo predominantly feature that variety; its two most frequent blending partners are Mazuelo, which brings color and additional alcohol to the finished wine, and Graciano, which adds acidity. Garnacha is also used, especially in Rioja Oriental, and it provides both fruit flavors and alcohol.

Tempranillo goes by aliases in Ribera del Duero, including Tinto Fino and Tinta del Pais. Locals claim that, due to climactic conditions, the grape has developed characteristics that render it completely different from Tempranillo grown elsewhere, producing a fresher, more elegant style of wine.

Most wine made in Ribera del Duero is 100% Tempranillo. However, it only has to have a minimum of 75% Tempranillo, and can also contain Cabernet Sauvignon, Merlot or Malbec, as well as smaller amounts of Garnacha Tinta or Albillo Mayor. The first four grapes each bring acidity, tannin and fruit to the blend, while the last, a white grape, adds fragrance.