The Combe de Biaufond

Biaufond is a surprising place. At the same time, it is an idyllic place renowned for years as a destination for a walk during summer. As well, it is a place steeped in history and which experienced unusual moments during the last war.

Moreover, many people are unaware that after the creation of the canton of Jura in 1978, the common border between this canton and the canton of Neuchâtel, represents only a distance of 250m. This common border is in fact a very small section between the canton of Bern and France. If one is in Biaufond and look beyond the homonymous lake, one will notice a boundary stone in the middle of the water. This milestone marks the border between France and Switzerland. Why is it in the middle of the water? One has to go back in time (to the beginning of the 20th century) to realize that the construction of the Refrain dam, inaugurated in 1909, considerably changed the appearance of the Doubs at this location. Indeed, where Lac de Biaufond is currently located, this river flowed some 10m lower than the current water level.

Biaufond is also at the end of the homonymous vale which is nothing other than the valley dug by La Ronde, the stream flowing from La Chaux-de-Fonds. One must use the imperfect because, even if it is certain that it was this stream that dug this valley, the current flow of the water is not clearly established. A few coloring trials had been carried out in the middle of the last century, but with contradictory results.

A path goes up the Combe de Biaufond. This one is, unlike the paths in the region, marked as a mountain path (therefore mark-signed in white-red-white). In addition, at each end of the Combe de Biaufond trail, a warning sign has been posted calling for caution. It is also specified that the path is reserved for people who are free from vertigo. Even if the warning may seem exaggerated, it makes sense considering that most of the other surrounding trails are pedestrian paths that do not require special skills. It is therefore understandable that it is sought to prevent inexperienced practitioners from venturing on this trail.

Leaving from Biaufond, the Combe de Biaufond trail runs a section alongside La Ronde, which at the end of the Lac de Biaufond forms a small body of water. The path, at the beginning, does not present any marked uneven ground. It is only when the gorge changes direction that one finds oneself faced with a few ladders and bridges to overcome the first lock. From this point, the path becomes a little more uneven, changes the bank of the valley and climbs towards a cave whose entrance arch can be seen from afar. After the cave, one changes banks again before reaching a very devastated-looking section of the gorge. There are felled trees and blocks of rock piled up pell-mell and it is difficult to understand whether the devastation is the result of a landslide or if, on the contrary, trees have been felled, which has favored erosion. After two small bridges and a change of bank, one reaches a basin from which one can clearly see the continuation: high ladders allowing one to get out of the gorge.

The exit from the gorge by the ladders is made necessary because, higher up, an old landslide has completely devastated the valley. It is this landslide that is at the origin of the Cul des Prés lake. This body of water is very variable in level and, depending on the year and the season, one can see water almost as up as La Planche.

On leaving the ladders one can continue in the direction of the Cul des Prés and, beyond, climb either to the Bois or to the Ferrière. Here, I had decided to take a good path leading to the Bas des Brandt. From this farm, it was then easy for me to follow a good path descending in the direction of the Doubs and reaching the bank of it at the Biaufond bridge.

Itinerary: Biaufond – Combe de Biaufond – Cul des Prés – Bas des Brandt – Biaufond
Distance: 6.5km
Altitude gain: 350m
Duration: 2h30