The Ariège (French pronunciation: [aʁjɛʒ] ^ⓘ; Occitan: Arièja; Catalan: Arieja) is a river in southern France, a right tributary of the Garonne.^[1] From its source in the Pyrenees near El Pas de la Casa, the river flows north, forming part of the border with Andorra, and passing through the following towns in two departments:

• In Ariège: Ax-les-Thermes, Les Cabannes, Tarascon-sur-Ariège, Montgailhard, Foix, Varilhes, Pamiers, Saverdun.
• In Haute-Garonne: Cintegabelle, Auterive, Pinsaguel.

Its longest tributaries are the Hers-Vif and the Lèze. It flows into the Garonne in Portet-sur-Garonne, south of Toulouse.^[1] Taken literally, the Latin origin of the river's name, Aurigera, indicates it to be a source of gold.