The Sentier des Ocres is a walking trail through the former ochre quarries just outside the village, and it is the main reason to come to Roussillon. Two circuits are available — 35 minutes and 50 minutes — both leading through sculpted ochre cliffs and formations that shift through every shade from pale lemon yellow to burnt sienna to deep burgundy. The scale of the old quarries gives the walk a slightly surreal quality: you are walking through industrial history that has been entirely reclaimed by colour and light.
There is a small entrance fee. Wear shoes you do not mind staining — the fine ochre dust settles on everything — and avoid white clothing for the same reason. The trail is open daily, with reduced hours in winter. Come in the morning or late afternoon for the best light; midday in summer is hot and the colours are less vivid. The trail is not strenuous, but the surface is sandy and uneven in places.