Approach

Drive up Valsavarenche to the parking in Pessey, (circa 1850m, 3kms before Pont) at the start of the path for the Chabod Hut, (signposted).

Ascent

From the parking use the bridge to cross the river Savara and follow the summer path W through the larch forest to the Lavassey alpage 2190m.  Go back to the right to follow roughly the zig-zag line of the summer path up the true right side of the Costa Savolera valley.  This leads to the Chabod hut 2750m.  Follow the moraine above the hut and then go up the Montandayné glacier firstly towards the Col de Bonney and then trend leftwards (NNE) towards the W ridge of the Herbetet.  Reach the Col du Grand Neyron and the bivouac hut by a right to left traverse.

Descent

By the same route From the Montandayné glacier instead of going back down to the Chabod hut, stay on the right going down to the Montandayné alpage 2460m and rejoining the ascent path at the Lavassey alpage 2190m. Descent by the Levionnaz Valley: From the col, follow the ridge, (exposed depending on snow conditions) to the W until you find steep E facing slope leading down to the Grand Neyron glacier.  Descend the valley on its true left bank until Levionnaz.  Be wary of the slopes above which face E and are liable to avalanche.  From Levionnaz, follow the summer route (No. 2) to reach Eaux-Rousses.  If Chaud river is snowed over and the avalanche risk is low then it is possible to descend this valley directly to the road. (see also: routes/221150/fr/col-du-grand-neyron-traversee-s-n)

The closest ski resort is Rhemes - Notre Dame , 8 km away.