In total, you'll find more than 20 high-altitude, off-piste trails here, with gullies and tracts of fresh powdered snow.
PIc Blanc
The best place to find off-piste skiing in Alpe d'Huez is from the top of the Pic Blanc Glacier. From here you will find plenty of couloirs to go down that all end up on the Sarenne path.
There are also plenty of other off-piste runs that will drop down from the top of the Pic Blanc, but these should only be attempted with a guide as you can end up in places that might require helicopter or a taxi to get back to Alpe d'Huez.
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On each side of the Poutran red run are large amounts of off-piste, but beware, the off-piste on the left (north facing) is extremely avalanche prone and shouldn't be attempted unless you have all the correct avalanche safety equipment, mountain knowledge and/or a guide.
Vaujany
Here is a black off-piste run called Roche Melon which is only open when conditions are good. It's never prepared by the piste crews and descends through the trees to eventually join a blue run called the Vaujaniate.
From Alpe d'Huez, you've also got the possibility of visiting the famous La Grave off-piste area.
La Grave
Not everyone staying in Alpe d'Huez will head to La Grave, or even want to, but it's worth a mention because it's a rare thing indeed to find an entirely off-piste resort.
Built in the late 70s, the Télépherique des Glaciers de la Meije takes you up into the high mountains in about 45 minutes. Once up there you'll find yourself in fine company. Freeriders from the world over travel to La Grave to enjoy this special mountain in its natural state.
If you plan to explore the glaciers, we strongly recommend you hire an Alpe d'Huez mountain guide - the risk of falling into a crevasse is real up here.
If you're not into glacier skiing, the classic routes down from the télépherique are a powder hound's dream, beginning on the rocky ridge between the glacier and La Meije. Below you, you'll find open snow fields, bowls, gullies, natural half-pipes, couloirs, forest skiing, steep and mellow terrain. The options are endless.
Beware, La Grave is a special place that demands respect. You shouldn't attempt to ski or ride here unless you have plenty of off-piste / backcountry experience.