The Mont Grêle lookout

Head to the commune of Attignat-Oncin and park in the cemetery car park (S).
From the car park go up the asphalt road to the hamlet of La Fauchère, cross though and reach the reservoirs (1) visible from above the hamlet.
Take the path, marked by a wooden sign, that rises sharply to the Rousse climbing 960 m in 45 minutes.
Cross the track and take the path slightly above (2). Always following the yellow signs, take the trail slopes in segments to reach 1360 m altitude at the “Sommet de l’Archelle" in 1 hour 45 minutes from the start and a 750 m drop (3).
As the viewpoint has disappeared, head north by the ridge trail to the Mont Grêle lookout point (1410 m), this 1.8 km trail has had 1/3 of its length gouged out by logging traffic. (4) The lookout point can be reached in 40 minutes and there is some information explaining the formation of the Épine massif and Aiguebelette lake, a nice view over Chartreuse and the two lakes.
Return to Archelle (3), and then pass through grazing fallow land and enjoy the views of the Chartreuse mountains especially Grand Som and Petit Som that can be seen nearby.
The downhill trail (5) the Chemin de la Pissoire is well marked, it indicates a two hour walk and Attignat-Oncin 5.9 km away by foot.
This grassy path quickly becomes a more difficult, furrowed at one part and gouged by 4x4 vehicles at another..
At 1170 m of altitude, “Chemin de la Pissoire" heads in the direction of the Pissoire falls (6). It's a steep and slippery path that will follow and cross the Pissoire stream at a small waterfall.
Reach a forest road (7), leaving it three loops in the road later (8) to rejoin first the trail and then the path, both following the course of the Pissoire stream, leading to Gerbezet (9) (630 m). From there, follow the GR9 following the first road and a path that goes along and across meadows. It will cross the Merderet stream (10) and, soon after, reach a small road down the left (11), then take the higher road right (12) to the village and car park (F).