In Arith, head to the hamlet of Montagny, then to the end of the road (car park).
(S/E) At the top of the car park, take the path on the left (towards La Platte - Prépoulain).
The path passes near a clearing with a barn in the centre, then heads south to the point at an altitude of 1140m.
(1) Before the path begins to descend (no entry sign), leave it and take a path on the right. It soon joins a sunken path that leads to La Plate.
(2) At this point, join theGR® du Tour des Bauges. Follow the wide stony track on the right (westbound), which quickly leads to a fence.
(3). Here you have two options:
Option 1 (the one described on the map; option 2: see the Practical Information section): if you want to go to the Curé altar after crossing the fence, leave theGR® and take a track on the right that heads towards the Chalets Regueras. Behind these chalets, climb up a path diagonally across a slope, then enter the forest until you come to a fence. Follow the fence, keeping to the left. From there, you will need a little patience and some searching to find the altar and the Croix de la Benoîte (the altar is about 200 metres from the Chalets Regueras).
(4) From behind the altar, follow the red arrow on a tree to the right of the altar, and a path will lead you to the Croix de la Benoîte. To rejoin theGR®, head northeast across the meadows The priest's room, a cave, is located 200 metres below the Pernet Chalet on the other side of the fence on the right. The cave is at the entrance to the small wood. Pass the Pernet Chalet and climb to the highest point at 1,438 metres. TheGR® is just below. (Thanks to plgrando for the details I added to the description).
The route on the map therefore passes by the Autel du Curé.
(6) At the Col de la Cochette, follow theGR® which climbs towards the viewpoint.
(7) Continue on theGR® and leave the Refuge du Creux de Lachat below on your left.
(8) Follow the suggested route carefully as the map does not correspond to the current terrain.
Keep following theGR® and the signs for Mariet-Dessus Montagny.
(9) TheGR® then takes a wide stony track and branches off to the left towards Montagny. Continue along this track, leaving theGR®, to reach the car park (S/E).