A splendid and sporty ascent through the forest to reach the gateway to the Vallée de Joux: the Marchairuz pass.
From the Bière train station, cross the village towards the Route du Marchairuz.
Leave the village and walk along the fields to the entrance of the forest. The climb starts a little further up, between the trees. Follow the yellow marks and arrows drawn on the trees. At some point you will cross the road to the Col before heading back into the forest to continue your climb. Once at the top, you will walk along the typical Jura pastures with their dry stone walls, before finishing your ascent between the trees, with some nice glimpses of the plain, Lake Geneva and the Alps in the background.
If you come by public transport, take the MBC train from Morges to Bière. Bicycles are transported free of charge on the MBC train.
For the return journey, be careful, there are buses only at weekends to go down from the Marcahiruz pass to Allaman.