I did this hike some time ago. However, I started from the center of La Chaux-de-Fonds and passed the Bikini-Test to go down the Combe des Moulins first. The first part of this hike is not very appealing, as you pass a quarry, a waste recycling and disposal plant and a sewage treatment plant. It is not very pretty, and it does not smell good.
Here, I avoided the Combe des Moulins trail by following a marked trail that branches off from the one leading to Haute Fie. This way, you walk through the most beautiful part of the valley, the Combe du Valanvron. You walk down towards Ronde to finally join the trail coming from the Combe des Moulins.
The Combe du Valanvron is sometimes narrow, and you can see water in some places, even though it is mostly hidden as it flows under the rocks.
When the valley widens, you join the trail coming down from Haute Fie. At this fork, you can follow a good trail leading to Ferrière.
When I did this hike, it had snowed a little a few days before. The atmosphere was therefore special. On the way up to Ferrière, I was able to observe a small herd of chamois.
Route: La Chaux-de-Fonds – Les Combettes – Sur la Combe – Combe du Valanvron – Ferrière Distance: 8.7km Elevation gain: 280m Duration: 2h30