What indicates on a bottle of Rioja DOCa the longest amount of aging?

In the context of Rioja DOCa, the designation that indicates the longest amount of aging is Gran Reserva. This classification is reserved for exceptional vintages that have undergone extensive aging both in oak barrels and in the bottle before being released to the market. Specifically, a Gran Reserva must be aged for a minimum of five years, with at least two of those years spent in oak barrels. This prolonged aging process ensures that the wine develops deep and complex flavors, often showcasing characteristics such as dried fruits, leather, and spices, while still maintaining an elegant structure.

The other classifications have shorter aging requirements. Reserva wines must age for a minimum of three years, including at least one year in an oak barrel, while Crianza wines require a minimum of one year in oak and a total aging time of at least two years. Joven wines, on the other hand, are typically released shortly after fermentation, with little to no aging. Therefore, Gran Reserva stands out as the most aged and complex expression of Rioja wines, making it the correct choice in this context.