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Nans-sous-Sainte-Anne is a French commune located in the Doubs department, in the Bourgogne-Franche-Comté region. Its inhabitants are called the Nanais and Nanaises.



Places and monuments
The village, thanks to its location at the confluence of several valleys which have deeply cut into the plateau, is a place with an exceptional landscape and a paradise for hikers, fishermen, climbing or caving enthusiasts. We find there :

Two resurgences:
Underground Verneau

The underground Verneau is an underground river in the Jura Franc-Comtois. It collects the waters of the Déservillers plateau and emerges at Nans-sous-Sainte-Anne before flowing into the Lison. It is one of the largest underground rivers in France. Containing few flooded parts, it is subject to sudden and devastating floods. The downstream escape (Baudin cave) can only be used at low water levels. Following several accidents, crossing requires authorization.

Fournier (1903-1912)
In 1898, Eugène Fournier, professor of geology at the University of Franche-Comté, explored the region's cavities. In 1903, he explored the Bousset Biefs until he found a first siphon that he thought was related to the cave of the Vieille Folle. He estimates the development of the diversion bays at two kilometers for a hundred meters of depth. He even gets lost for a moment. He then attacks the cave of the Old Fool, but is blocked at a hundred meters from the entrance by a deep pool. He returned there in 1904 with a dismountable 'Osgood' boat. The boat takes on water, their progress is interrupted by a wetting arch and the boat ends up capsizing. In January 1911, taking advantage of very cold weather, they resumed exploration with a boat in better condition (a Berthon). This time they manage to cross this first lake but come up against a waterfall that they consider impassable in the icy water. Back in June, in the dry period, they cross the waterfall and this time come up against a significant escarpment that they will not cross until April 1912. They reach a drowned joint that they believe to be in relation with the Biefs Bousset . During this period, Fournier, helped by his team, also explored the Gouffre de Jerusalem where he was also blocked not far from the entrance on a plunging vault, the Gouffre de la Baume des Crêtes where he probably reached the Réveillon room in 1903 (-100 meters), the Gouffre du Creux qui Sonne in Montmahoux which he explores until the first siphon in 1912. Finally, he visits the source of Verneau which can be penetrated for a few meters by low water and is convinced that it is in relation to the caves of the plateau and that a development should make it possible to make it a tourist attraction of the first order.

Between 1938 and 1969
In 1939, Charles Domergue resumed Fournier's explorations, but only discovered a new room in the Baume des Crètes. In 1951, the Dolois Speleological Group discovered a new room after a long clearing of the obstruction in the Baume. In 1949, J.-D. Cauhépé had tried to cross the first siphon of Biefs Bousset in apnea. In 1951, the Dolois set foot in the collector for the first time by forcing the wetting vault which had stopped Fournier in the chasm of Jerusalem. They will however be blocked a little further on a siphon. In August 1965, cavers from Greyl and CAF Pontarlier tried to pump the siphon from the Verneau source, which only dropped a meter fifty in two weeks before rising again in a few moments following a storm. We should also note the Salle des Suisses (discovered by the Swiss from the Val de Travers section of the SSS) in 1966. Some colorings by the Maurice Ravel Speleological Group, a member of which also engaged in freediving in the Verneau source. In 1969, Jean-Claude Frachon (S.C. Jura) and Pierre Pétrequin (G.S. Doubs) plunged into the siphon of the source for several tens of meters to a depth of 10 meters, the flooded gallery is vast, hope is reborn.

The explorations of the SHAG (1969-1984)

From 1969 and for 15 years, the SHAG (Société Hétéromorphe d'Amateurs de Gouffres) will be interested in the exploration of the underground Verneau and attack it from all the entrances. Since the beginning of the century, the equipment has progressed, cavers have used spits, blockers, descenders, have good mixed lighting (acetylene / electricity), dry suits and above all, cave diving has become possible without taking of unacceptable risks. In 1969, Christian and Yves Aucant realized that a suspended siphon of the Vieille Folle could be emptied by gravity. It will give access to 230 meters of new galleries, but above all, will reach a depth greater than the terminal siphon, suggesting that there are exposed galleries behind it. The colorings also suggest that water flows freely underground. In June 1970, a first, then a second siphon, were crossed by Yves Aucant and Pierre Pétrequin in the Vieille Folle. Jean-Pierre Urlacher passes a first siphon at the Biefs Bousset, followed by a second. In August, they reach the Verneau collector via the Vieille Folle and undergo a first flood on the way up. They are sudden and violent, it will discourage them from resuming explorations in La Vieille Folle for four years. In 1971, they crossed a second siphon in the Bousset Biefs, of which they immediately discovered a shunt. It is then the hunt for drafts, after some explorations and unobstructions, they set foot in the active collector, which they can follow for about a kilometer, on June 5, 1971. The following days, they explore further. the collector and its tributaries. That year, the other caves are explored, cleared, pumped, dived but nothing leads to spectacular discoveries. Clearance work to bypass the Biefs Bousset siphon, which is an obstacle to exploration, was undertaken in October. This work ended on February 22, 1972, allowing access to the collector for non-divers. In January 1972, the collector was reached by the Baume des Crêtes.

Many climbs are attempted to discover a junction between the Biefs and the Vieille Folle. In vain. It is finally by a new siphon that the junction will be carried out on May 21, 1972. Several dives also make it possible to extend the exploration of the chasm of Jerusalem. On August 25, 1972, the downstream siphon of the collector at the source of Verneau was crossed (230 meters) and the good weather conditions in summer 1972 allowed the exploration of more than 7 kilometers of galleries (in 9 expeditions). The siphon, which had become dangerous, was cleaned of its many Ariadne's threads left by previous explorations and damaged by the floods. It is re-equipped correctly with the electric cable. In 1974, work resumed in the Vieille Folle and, on February 15, 1975, the junction was made with the Biefs Bousset and the resurgence of Verneau. The network now has 18 kilometers of development and 352 meters of vertical drop. On July 17, 1976, it was the chasm of Jerusalem which in turn joined. A first crossing between the Vieille Folle and the source was made in October 1976 by two teams who crossed in the middle.

On October 1, 1977, it was the turn of the Baume des Crêtes to be joined with the Jerusalem chasm, the difference in level reached 387 meters for a development of 27,600 meters. In October 1978, television was invited to La Baume des Crêtes (Antenne 2 - Mi-Fugue, Mi-Raison). In November, a Biefs Bousset - resurgence crossing is completed in 15 hours (diving tanks were placed upstream of the siphon the day before).

It was not until 1983 that the siphon on the side of the Patafoins room was bypassed and made a large part of the network accessible to non-divers. To facilitate the exploration of this network, which has become very large, a bivouac was set up in September 1983 at the outlet of the Vieille Folle, it will facilitate the exploration of the Creux qui Sonne tributary which was reached on July 14, 1984.

In the meantime, speleologists from Nans-sous-Sainte-Anne helped others from G.S. Doubs and firefighters from Besançon managed to bypass the terminal siphon after having widened many passages in the Baudin cave. In times of low water, it is now possible to exit from the bottom. On August 6, 1984, Yves Aucant, Alain Couturaud and Patrick Pelaez made the first crossing of the network (Biefs Bousset-Baudin) without diving.


Caving since 1984
In June 2011, the network had a development of 33,300 m and 35,000 m in 2015 for a height difference of 387 m.


The source of the Lison

The source of the Lison: a resurgence opening into a cave and then falling in a waterfall that never dries up. Nearby, there are two karst "monuments": the Creux Billard, a chasm over 80 m deep and the Sarrazine Cave, an arcade 100 m high and 30 m wide.



The village, located 365 meters above sea level, is located at the confluence of seven valleys (those of Lison upstream, Lison downstream, Arcange, Bief de Vaux, Bief de Foure, Verneau and Prés Prin ) which deeply cut the plateau which culminates at an altitude of 700 m.



Nans in 1145; Nan in 1315; Nant in 1410; Nan deçà de l'eau in 1614; Nans-sous-Sainte-Agnès in the 18th century.

Located in a characteristic remote Jura, surrounded by cliffs and near the source of the Lison, painted by Gustave Courbet, the name of the town comes from the Gallic "nanto" which designates a valley (often steeped in), a river, or a torrent. .

Spelled nan / nans / nant or nanc-, this word is very present in toponymy5 especially in regions of limestone relief, where it is found associated with more or less narrow and deep depressions that one meets there, as in the case of de Nant (Aveyron), Nantua (Ain) or Nancy (Meurthe-et-Moselle) and in this case.

The root "nanto" is also particularly frequent in the Jura (cf. Gondenans-les-Moulins, Nans, les Nans, Mournans-Charbonny, Nanc-lès-Saint-Amour, Nance, Nancuise, Nantey). It is also the basis of family names like Nantet or Nantel.



On the territory of the municipality, some vestiges of the castle of Montrichard remain. It consisted of a high tower protecting a set of annex buildings. A ditch cut in the rock isolated this small promontory on the west side.

Built in the 13th century to watch over the medieval path leading down from Montmahoux, it was totally ruined by the troops of Louis XI around 1479.

In the course of the fourteenth century, it housed a ducal counterfeit workshop.

Meager are the vestiges of it today. Only a trained eye can distinguish a few elements.