Airén is a variety of white grape used to make white wine, and is the most planted variety of grape in Spain, particularly in the region of La Mancha.
The Airén vine has an unusually low vine density (around 1500 vines per hectare), and so its vineyards cover more area than any other grape variety in the world. However, as trends move towards red wine, a huge number of the vines are being uprooted, not least because the grape produces an acidic and characterless wine. A consequence of this is that its principal use has generally been in the manufacture of brandy and port.