Rioja wine comes from the Rioja region in northern Spain, which is divided into three sub-regions that contribute to diversity in Rioja wines. The primary grape varieties used are Tempranillo, Garnacha, Mazuelo, and Graciano. Rioja wines are classified based on aging into Joven, Crianza, Reserva, and Gran Reserva categories indicating minimum time spent aging in barrels and bottles. Oak aging imparts flavors like vanilla and spice, while terroir influences different wine styles depending on factors like grapes and sub-region.