Park in the visitor car park on Chemin de la Chapelle: coming from Colonzelle, on Avenue de la Gare, turn right at the entrance to the village. Coming from Grignan, after the town hall, turn left onto Avenue de la Gare, then left after the Bistrot de Pays.
(S/E) With your back to the chapel, walk up towards the old village. Cross Avenue de la Gare and continue straight ahead on Rue de l'Église.
(1) Take Grande Rue on the left. Go up to the foot of the tower via the second street on the left. Once at the foot of the tower, go down the stairs on the left.
(2) Turn right onto Rue du Coustias, then right again onto Chemin de la Rousselle.
(3) Go down to the left between two dry stone walls. Continue downhill on the Clos des Serrières path. Cross the Route Sous la Gare to go up opposite, then turn right at the foot of the hill onto a path that crosses a wood. Join a wide path, Chemin des Barquets.
(4) Turn right, ignoring the various paths branching off to the right and left, until you reach the small tarmac road, Chemin des Souterras.
(5) After about 100 metres, leave the road and climb left up a rocky hill. Follow the well-marked path through the undergrowth. Take thefirst path on the right and return to see a drystone shelter (access visible on the standard OSM map). On the way back, continue to the right. Ignore asecond path on the right and take thethird one for a round trip to a second drystone shelter. On the way back, continue to the right. At a bend in the path on the right, a rocky platform offers a view of the Château de Grignan and the La Lance mountain. You can see the Lez river below. When you reach a triangle formed by the paths, keep to the right to discover a third drystone shelter. With your back to the drystone shelter, continue to the right. You will come to a steep, rugged descent. At the bottom of this descent, keep to the left at the fork. At the next crossroads, take a detour to the left to reach the right bank of the Lez river.
(6) Opposite, on the other bank, rises the cliff where the old millstone quarries are located. The route passes along the left bank. Retrace your steps and continue left, then left again onto the Chemin des Souterras. Soon make a detour to the right to see a very pretty drystone shelter built into a dry stone wall and covered with ferns. On the way back, walk about 25 metres and choose to continue to the right between two low walls or to the left, overlooking the Lez (take care). The two parallel paths join together. At the next two forks, keep left (mountain bike signs 2, 8 and 9). The path crosses a ditch. On the left, you can make a detour to the edge of the Lez. Continue to the right until you reach a footbridge.
(7) Cross the ditch via the footbridge. Continue along the path, keeping left twice (mountain bike signs 2, 8 and 9). Follow the Chemin des Souterras, which widens, passes under the Domaine de la Chamarade (campsite), climbs over rocky slabs and leads to a carriage road opposite, then to a small tarmac road, the Chemin des Chamblas.
(8) In front of house No. 95, in the commune of Montségur-sur-Lauzon, turn left until you reach the "Give Way" sign and continue left, along the edge of the D481 (Route de Valréas, caution!). Just after the bridge over the Lez, turn left onto the road and continue along the left bank of the Lez.
(9) At the foot of the hill, turn left and continue straight ahead.
(10) Just before a private property, leave this track and climb up to the right onto a path that crosses some rocky slabs before turning sharply left. Ignore the paths branching off to the right and continue along the path above the Lez. Several viewpoints on rocky outcrops will appear, offering views of the right bank (first part of the route) and the Tour de Chamaret.
(11) When you reach a rock, leave the main path and descend to the left of the rock on steps carved into the stone. Please note that from this point onwards, the terrain becomes more uneven. At the bottom of the steps, keep to the right. Continue carefully, choosing the easiest route between the rocks.
(12) You will reach the old millstone quarries in the cliff opposite point (6) on the route. Climbing routes are visible just above the rocky outcrop. Continue along the main path to avoid the steep shortcuts. The path will climb and descend several times, offering access to the Lez river here and there .
(13) At the junction indicating the continuation of the fitness trail on an uphill path to the right, ignore this start and continue opposite along the Lez. Several pieces of equipment mark this part of the route. Stay on the main path, which widens, passes over rocky slabs and through sand.
(14) At the T-junction, continue straight ahead. Pass the sports fields and the Jardins Partagés car park and head up towards the village of Colonzelle on a small tarmac road.
(15) Turn left onto the D231 (Route de Margerie). Cross the bridge over the Lez and follow the D471 (Route de Chamaret, caution!) for about 150 metres. Turn right onto a wide path towards the pumping station. At the fork, take the MTB 8 signpost on the left to pass between cultivated fields. (The path may have been damaged over a few dozen metres by agricultural vehicles).
(16) Join the TGC discovery route by passing between two walls, under the old railway line (read the information panel). At the next junction, turn left (mountain bike signs 2, 6 and 8), then straight ahead, crossing the "Chemin des Basses Rouvières".
(17) When the path emerges between two mounds of earth, turn left (mountain bike signs 2, 6, and 8) then keep right at the next fork to join the small tarmac road "Chemin du Tramway" which becomes "Chemin de la Chapelle". Pass near the Saint-Barthélémy Chapel and join the nearby visitor car park. (S/E)