Starting from the village of La Voûte in the commune of St Germain de Joux, you climb the Col de Bérentin (1,144 m) on the north side, through coniferous and deciduous forests. Heading for Lalleyriat on the D55, you'll reach the village of Le Poizat, a site dedicated to Nordic skiing in winter. 5 km further on, you'll cross the Col de Bérentin, which links the Nantua valley with the Bugey highlands. A steady 12 km climb, but quite steep with a maximum % of 6.8% and very little traffic.