Park in Place Gilles Léontin.
(S/E) At the eastern end of the square, turn right onto Rue du Barri, continue along Rue Gaston Raousset until you reach a hairpin bend.
(1) Before crossing the small canal that used to bring water to the castle, turn right and follow the stream. Pass the spring and go up the Saint-Michel valley, following the yellow signs.
(2) At the top of the valley, after a 2 km climb, at the crossroads of the carriage roads, take the road opposite and leave it after about 100 metres to take a path on the left. The path climbs and passes close to the Rochers de Raous (3 km), the highest point of the Montagnette.
(3) Walk to the rock and back to admire the view. Follow the path downhill, crossing the DFCI track three times, until you reach the abbey. At the reservoir, turn right and enter the abbey grounds from the south.
(4) Cross the buildings, pass in front of the abbey church and exit through the north porch. Return to the path, pass the car park and the reservoir and continue along the carriageway until you reach the first hairpin bend.
(5) Here, ignore two paths and turn right at the third towards the west. At the first fork, turn right at a right angle and head north for 1 km.
(6) When you reach the DFCI road, turn right, go through the gate and join the D81. Continue straight ahead on the road.
(7) At the left-hand bend, take the path that heads straight north. Pass the houses of Les Bouisses and continue straight ahead. At the crossroads (elevation 59), continue left, then right onto the path.
(8) Turn left and continue to the Croix de Saint-Julien. Then descend into the valley via a faint path heading due west. You will come to a small canal, which you follow for a few metres until you reach a bend in the road to Barbentane.
(9) Follow it to the left for about 800 metres, passing a pumping station, and arrive at the Y-junction at the Croix Coupée.
(10) Head back east, turning left onto the D81. After 200 metres, take the path on the right that leads to the Chapelle Saint-Julien.
(11) Continue along the path heading south into a steep-sided valley with very dense vegetation. At the end of the woods, climb a fairly steep slope. 700 metres after the chapel, leave the valley.
(12) Look for a path climbing up to the right, which will take you to the ridge of Moulon de Blé. Turn left and follow the ridge to the summit (153 m).
(13) Descend via the path on the left until you reach the DFCI road. Take this road on the right. At the second hairpin bend, take the path that leads to Moulin Bonnet.
(14) Go back a little and descend on the path that arrives in front of the castle entrance. Continue on Rue Gaston Raousset, which you took on the way there.
Next, take a short tour of the village of Boulbon. To do this, turn right and join Rue du Four Banal. At the end, turn left, then left again into Grand Rue. Finally, turn right onto Rue Saint-Christophe to return to Place Léontin (S/E).