Arabaux is some 20 km south of Pamiers and 2 km north-east of Foix, which is the urban area to which it belongs. National Highway N20 passes through the south-western corner of the commune partly in a tunnel but it has no exit in the commune with the nearest exit being No. 10 south of Saint-Jean-de-Verges. The D1 road goes from Foix through the south of the commune and continues east to Carla-de-Roquefort. Access to the village is by country roads - one from the NR20 Exit 10 and one from the D1 on the eastern border. The commune is heavily forested in the centre and west with the rest of the land farmland.[3]
The Alses river passes through the centre of the commune from east to west then turns north forming part of the western border to join the Ariège near the NR20 Exit 10. The Ruisseau d'Araboux rises west of the village and flows north-west to join the Ariege.[3]
