From Marseille Provence airport, A51 to Pertuis / Venelle (exit)
La Tour d'Aigue, Grambois, direction Forcalquier, (at the crossroads)
Saint-Michel l'Observatoire, D5 Revest-les-Brousses.
If around the A7 highway, see the Orange, Carpentras, Sault, Banon, Revest-les-Brousses (carpentry) exit on the left before the Revest-les-Brousses intersection.