When entering Maison Neuve via the D104 and from the north, turn right towards the church and park a little further on behind the cemetery.
(S/E) Take the Chemin de Chamviel northwards. After the junction with the Chemin de Bel Air, a yellow-marked path goes straight ahead while the Route de Chaulet goes to the right.
(1) Reach the cliffs overlooking the Chassezac via this path, which then descends to the plain near the river. Reach Chaulet via a wide path. Cross the hamlet and climb up to a large bend with a wide view of the gorges. Continue for about 50 metres after this bend.
(2) Turn left. The cliff path slopes slightly downwards to the left, then crosses a small valley and climbs back up to the top of the cliffs. Continue to a flat area.
(3) Keep to the left and descend to gradually approach the rocky chaos, which becomes increasingly impressive and wooded as the slope becomes steeper. Finally, begin a more gradual ascent to follow and cross the Ceyrèdes ravine and join the D452, the Casteljau road (to climb up to the D452, do not follow the yellow markings and turn left, but take the unmarked path on the right).
(4) Follow the road north for a few hundred metres. When it turns sharply to the left, a wide path continues straight ahead.
(5) Take this path, which crosses the Ceyrèdes stream again, then passes to the right of a beautiful dry stone barn (La Gleyzette). Continue for about 800 metres until you see the first drystone shelter on the right.
(6) At the crossroads, turn right (signposted) to reach a larger drystone shelter. Then continue in the same direction to reach a wider path.
(7) Turn left and rejoin the main path you left earlier. Continue to the right, heading north, until you reach a large crossroads with several paths.
(8) Take the path furthest to the right, heading south-east at the start. Pass the buildings on your right. A little further on, on the right, there is a pretty round drystone shelter, which has unfortunately been damaged recently (the lintel has collapsed and had to be bricked up). Further on, on the left, in a depression (elevation 219), is the Saint-Arnaud karstic cave, a karstic cave whose size and depth can be guessed at amid the lush vegetation. 200 m further on, you will come to a T-junction (you can make out an old, overgrown drovers' road in the direction you have just come from).
(9) Leave the marked trail and turn right towards the south (despite a yellow/white cross), towards the first houses. Gradually reach a small tarmac road. Continue to the Coudon crossroads. Leave the hamlet of Coudon on your left and the Montchamp road on your right and continue straight ahead on the small road.
(10) Walk past the hamlet of Les Buis on the right-hand side of the road (recent wooden buildings), then its car park on the left-hand side of the road (in the left-hand bend), and continue along the same road to reach Maison Neuve and the car park (S/E).
: at number 3, just after passing the Ceyrèdes ravine (dry at the moment), we come to a small fork where the signposts direct us to take the left-hand path. However, you need to take the very small path that goes up to the right to arrive directly on the D 452 (and not 542, unless I'm mistaken). This is probably the detour that someone else mentions in one of the comments.