The starting point is at the Marcale roundabout car park in Saint-Péray, which can be reached by car via the Route du Puy-en-Velay.
It is also possible to reach the starting point by taking the bus from Valence to Saint-Péray (line C4) and stopping at the Hôtel de Ville or Jeanne d'Arc stops, both of which are equidistant from the starting point.
(S/E) Go around the roundabout and take Rue de Marcale for about 500 metres.
(1) Before the end of this street, turn onto the track below Château du Brét and continue for about 500 m until you turn sharply to the right. Leave the track and take the very steep path running parallel to it, climbing until you reach the central path of Crussol. At this crossroads, take the path that climbs to the left until you reach a platform. Follow the sign for "Site d'escalade Top Secret" (Top Secret Climbing Site) along a steep path to the right.
(2) At the climbing site, look for the marked PR® path on the right-hand side of the site and follow it to the summit of Crussol, at a place called Haut de Chandarcet.
(3) Follow the GR®42 trail to the left towards Crussol Castle.
(4) Leave the GR®42 shortly before the castle via a bypass path that branches off to the left under the ramparts, and walk a few hundred metres until you rejoin the GR®42 below. Note that it is entirely possible – and even recommended – to follow the GR®42, which passes through the castle interior via the most remarkable points. The choice of this route outside the castle simply allows you to complete the circular route more quickly. Continue on the GR®42, descending to the left. When you reach the car park, continue to follow the GR®, which descends via a staircase and then a wide path to the Château de Beauregard.
(5) Continue on the GR® trail, which leaves to the left of the castle and leads back to Rue de Marcale. Turn right to return to the car park (S/E).