Rioja is divided into three sub-districts - Riojas Alta, Alavesa and Baja - and the varying conditions within each suit different grape varieties. Grapes from all three can be blended together.
Red Rioja is often a blended wine and four grape varieties are traditionally permitted. Tempranillo is usually the most prominent and imparts the fresh fruit flavours, whilst Garnacha (Grenache) provides body and Mazuelo (Cariñena or Carignan) and Graciano are there for warmth and finesse. Once the wine is fermented (usually in stainless steel) and blended, it is almost always introduced to oak (those that are not are classed as joven or sin crianza) and then aged in the bottle. This is strictly regulated. A crianza wine must spend six months in oak and eighteen in the bottle, a reserva has been in oak for a year and will not be released until its fourth year, and a gran reserva is six years old when it goes on sale and has spent eighteen months in oak.
The white wines are made from Viura (known as Macabeo in France), Malvasia and Garnacha Blanca. They are usually fermented in stainless steel and are often meant to be drunk young and fresh, but some examples are rich and perfect for aging.
The three sub-districts of Riojas Alavesa, Alta and Baja have differing climates and soil types that allow the whole variety of grapes to thrive. Details of these can be found in their relevant sections.
Both 2001 and 1998 are considered to be exceptional vintages and 2003, 2002 and 1999 were all judged to be good. Wines from these years are still readily available.