The Grotte du Portel (or Grotte de Campagna or Caire) is a prehistoric decorated cave located on the territory of the commune of Loubens, Ariège, in France. The cave is part of a karst system of the Plantaurel massif, in the foothills of the Pyrenees.

The occupation of the cave by prehistoric men is found in two distinct parts of the cave:

• The central and south-eastern sector or "Portel-Est", known as the "decorated cave of the Portel": its main period of occupation is the Middle Magdalenian, the parietal works of this cultural facies are in all the galleries; The correlation between wall images and sounds (archaeoacoustics) is particularly notable.
• The "west" or "Portel-west" sector: this part of the cave has a stratigraphic sequence containing Mousterian, Châtelperronian and Gravettian.