The gorges of the Flumen

This path - which can be steep and which is today narrow and ravined in places - was the main communication channel between Saint-Claude and Septmoncel up until 1884, when the “route des lacets” from Septmoncel through the famous Gendarme’s hat was built.

During the 19th century, valleys were transformed into real “industrial boulevards” in which modest workshops and major factories can be found and where several types of production either cohabited or succeeded one another. Fulling mills, grain mills, sawmills, wood turning factories, diamond factories, etc.: several hamlets underwent industrial growth and changes in names, sometimes resulting from the rapid change in rural differences. Thus, the hamlet “la Patinerie”, in the municipality of Villard-Saint-Sauveur, became “Montbrillant” in 1885 to reflect the new diamond industry that had developed in the High-Jura.

The Flumen - which means “river” in latin - is actually nothing like a river. With its impetuous torrent, which can be quite impressive during periods of heavy rainfall, it is fed by the runoff water from the Lamoura lake and the Hautes-Combes. The Flumen waterfalls spurt out into a dark and wild cirque.

Dark grey in colour, the wallcreeper is almost invisible on the rocks when immobile. Its flaming red wings bring colour to the cliff when it spreads them to flit against the rocks, giving it the name “wallcreeper”.  When hunting for insects and spiders that it catches in cracks in the walls using its thin curved beak, this bird tirelessly jumps, crawls and flutters around the cliffs. But in the summer, you won’t see it here, as it has already retreated up into the mountains. Your only chance of seeing this bird is between autumn and spring.

The view from this belvedere, which can be seen from Sur les Grès, overlooks the Flumen wind gap, cut into the Sur les Grès anticline. By digging deep gorges at the same time folding occurs, over tens of millions of years, the river has created a perfect cut into the many geological layers that are well visible on the Sur les Grès anticline upfold and shows the very core of the Jura’s folds.

I'ts difficult not to notice this peculiar fold, almost folded in on itself. It is in fact a “secondary” or disharmonic fold, arising due to the overlapping of the Molunes anticline over the neighbouring Septmoncel valley syncline. This is a remarkable example of hard rock’s ability to bend over time, and even over millions of years, under considerable pressure. 

This bird from the swallow family nests in the cliffs, sheltered from the overhangs. But in the Flumen valley, some couples live in the tunnel of the “route des lacets”, also called “Roche percée” (the drilled rock). Near Morez, the crag martin has even used the famous archways of the viaducts as a home.

This viewpoint overlooks the landscapes in the classified site of the Gorges of the Flumen. From the summit, you may see a peregrine falcon or a golden eagle flying graciously overhead. The golden eagle builds one or several nests in steep areas, on the side of a cliff or in a tree on a steep slope. At the end of the winter, it may put on impressive shows in the air. In the summer, it is more often seen tirelessly scouring for food.

The common raven is the largest passerine bird in Europe. It is well-known as an inhabitant of the Tower of London where their disappearance would mean misfortune. In the Jura, this bird can mainly be found on the cliffs, near the peregrine falcons.  Its call can be heard from as early as February.

Calcareous grasslands are home to many species of plants, the most famous of which are orchids. These flowers demonstrate their significant ability to adapt. Most are pollinated by insects, when very few even produce nectar! To ensure its pollination, the burnt-tip orchid has adapted by imitating other nectar-producing plants. Their inner petals are adorned with colourful designs that converge towards the centre of the flower and tell the insect where to land. An actual landing strip! But the insect leaves empty handed as the flower doesn’t have any nectar to give. Still, it makes the most of the insect’s visit to cover it with pollen, which it will then take to another flower.