Usually jammed with skiers and hikers, this excellent hostel is right below the Puy de Sancy cable car, 3.5km south of town. Facilities include squeaky-clean two- to six-bed dorms with en-suite bathrooms, a guest kitchen and laundry, bike sheds, ski and snowshoe rentals, and an in-house bar. Book way ahead in winter, especially for one of the seven double rooms.
You'll need a FUAJ card (hostelling international membership) to check in; they're available at the auberge (€11).