Vercors Massif

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Vercors
Looking north from the highest point
The view to the north of Le Grand Veymont
Highest point
Peak Grand Veymont
Elevation 2,341 m (7,680 ft)
Coordinates 44°52′12″N 5°31′37″E / 44.87000°N 5.52694°E / 44.87000; 5.52694
Dimensions
Length 60 km (37 mi) North
Width 40 km (25 mi) West
Area 1,350 km2 (520 sq mi)
Geography
Vercors Massif is located in France
Vercors Massif
Country France
Region Rhône-Alpes
Range coordinates 44°58′N 5°25′E / 44.97°N 5.42°E / 44.97; 5.42Coordinates: 44°58′N 5°25′E / 44.97°N 5.42°E / 44.97; 5.42
Parent range Alps
Vercors, Glandasse

The Vercors Massif is a range of plateaux and mountains straddling the départements of Isère and Drôme in the French Prealps. It lies west of the Dauphiné Alps, from which it is separated by the rivers Drac and Isère. The terrain is rugged beyond what the common epithet "plateau" would indicate, and the mainly limestone foundations have created peaks, valleys, gorges, cliffs, and dales - cliffs at its eastern edge face the city of Grenoble. This complexity has led to the area being divided historically into several different regions - the "Quatre Montagnes" (four mountains), the "Coulmes" (gorges), the "Vercors Drômois" (Drome Vercors), the "Hauts-Plateaux" (high plateau) and, in the foothills, Royans, Gervanne, Diois, and Trièves. It has received the nickname the "Fortress".

This complex geography explains why until recently the massif lacked a sense of unity, the economic changes and movements taking place between the mountains and the plains rather than between the different parts of the mountains. The use of the word Vercors to describe the whole region is itself somewhat of a novelty - up until the mid-twentieth century the term applied only to the township of La Chapelle-en-Vercors (connected to Royans), and the northern area around Lans-en-Vercors, Villard-de-Lans, Autrans, and Méaudre (connected to Grenoble) was known as the Four Mountains area. The region became noteworthy during World War II when the Maquis du Vercors led the French Resistance against the German occupation and established the Free Republic of Vercors in June and July 1944.

The plateau's karstic area includes the famous Vercors Cave System which includes Gouffre Berger. The Vercors has several resorts for cross-country skiing and for down-hill skiing. Villard-de-Lans is the biggest down-hill ski resort. This sporting area is environmentally protected, and although the natural environment has been drastically altered throughout history for the purposes of agriculture and forestry, plans for afforestation will make it one of the major forests of Metropolitan France and a reserve for species such as the Southern Tulip and Black Grouse, two symbols of the park, as well as the re-introduced Griffon Vulture and the Alpine Ibex. The differences in climate and altitude across the Vercors are reflected in the high level of diversity in the fauna and flora.

Etymology[edit]

The Massif du Vercors derives its name from the name of a local tribe who lived in the area at the time of the Roman conquest of Gaul, who were known as the Vertamocorii (or Vertamocori, Vertacomicorii, Vertacomocorii), a name meaning excellent troops (or possibly troops of the summit).[citation needed] Modern inhabitants are referred to as Vertacomiriens, a name remarkably similar to that of ancient times.

The use of this appellation to describe the region first appeared in the 20th Century - prior to that it was used in description of the upper valleys of the Vernaison in the township of La Chapelle-en-Vercors. At the start of the 20th Century, Henri Ferrand explored the massif, taking numerous photographs, publishing books, and describing the geology of the mountains, although relating mainly the human geography through the telling of stories; Ferrand was the first to use the term Vercors in its contemporary sense, but the geographers Raoul Blanchard and Jules Blache were responsible for popularising it in the late 1920s and early 1930s. By the latter half of the century, the term was ubiquitous.

Geography[edit]

Location[edit]

The Vercors is a massif in the Prealps, in the south-east of France, straddling the departments of Drôme and Isère, both part of the Rhône-Alpes region, about 100 kilometres (62 mi) south-east of Lyon. Covering an area of 135,000 hectares (520 sq mi), it has a north-south length of 60 kilometres (37 mi) and an east-west width of 40 kilometres (25 mi), making it the largest region of the northern prealps.

It is surrounded by the Chartreuse Mountains to the north, the Matheysine area of the Dauphiné Alps to the east, and the Diois Massif to the south. It is with this that it shares its only geographical connection, in the far south-east in the form of the 1,457 metres (4,780 ft) col de Menée. It is drained in the north-east and north-west by the Isère river, in the east by the Drac, and in the south by the Drôme. The western side overlooks the Rhône Valley.

Topography[edit]

Geomorphology[edit]

DEM of the Vercors massif

The geography of the Vercors is often summarised by the term "plateau". From afar, this seems obvious - the difference in altitude between the massif and its valleys is a few hundred metres, whereas the difference to the more densely inhabited areas around is between 800 metres (2,600 ft) and 1,200 metres (3,900 ft). The crest of the eastern edge has several summits over 2,000 metres (6,600 ft), and the interior of the Vercors mainly varies between 800 metres (2,600 ft) and 1,500 metres (4,900 ft).

On closer inspection, the contrasts are important: wide valleys (the valley of Lans-en-Vercors, the regions around Autrans, La Chapelle-en-Vercor, etc.) and plateaus (forêt des Coulmes, forêt de Lente, and the immense Vercors high plateau) are separated by deep grooves in the landscape (the Bourne and Furon gorges, for example), with imposing cliffs often exceeding 400 metres (1,300 ft) (for instance in the Combe Laval or the Cirque d'Archiane). Mont Aiguille stands apart from the rest of the massif due to massive erosion that has occurred on all sides.

Due to the relief, many parts of the Vercors are isolated from the rest of the range. For example, Gresse-en-Vercors is not connected with the interior and so to reach the southern parts a journey of 100 kilometres (62 mi) via the col de Rousset is required; to reach the northern parts necessitates a journey of 70 kilometres (43 mi) via Saint Nizier-du-Moucherotte. The villages at the far northern end were cut off from the rest by a landslide near the Mortier tunnel - since the route has not been repaired, nor are there plans to, residents must descend to the plains and ascend back up by a different route if they wish to access the other parts of the range. The Peuil plateau, in the east, is also not connected. This plateau is evidence that during the Ice Age, the Grésivaudan glacier reached that altitude leaving a swamp/marsh. It is also one of the places from where, with clear weather, Grenoble can be seen between the Chartreuse and Belledonne.

The particular relief has earned the area two nicknames - firstly, that of "the fortress" in reflection of the difficulty of access and the need for visitors to pass through gorges with limestone cliffs, and secondly, that of the "french dolomites", in reference to the Italian massif known for its geological formations.

Sub-divisions[edit]

Topographic map with the different parts of the Vercors

Due to this unusual relief, the centre of the Vercors is divided into several distinct regions.[1]

The coulmes, in the north-west, have always been the part of the massif which was most heavily covered in forest. This was exploited in the nineteenth century for the production of charcoal, especially by Italian immigrants. In this region, the Vercors resemble more a mountain than a series of plateaux, with the folds of urgonian limestone being more rounded. Several impressive roads allow access to the coulmes, especially the roads through the gorges du Nan, and the gorges des Écouges.

The four mountains area is today the most heavily developed area for tourism, especially for cross-country and downhill skiing. This area is very popular with those from Grenoble for weekend excursions. Nonetheless, traditional activities still take place in the Four Mountains, in particular the breeding of dairy cows and the production of cheese. The four main villages, Autrans, Méaudre, Lans-en-Vercors, and Villard-de-Lans, are separated into two plateaux by wooded hills. These four villages are ski resorts but still today possess working farms.

The Drômois Vercors is made up of smaller but more numerous plateaux. Some of these are spectacular (Ambel, Font d'Urle), and offer beautiful views both of the others and of the surrounding lowlands. In the north of the Drômois Vercors there are several gorges which are traversed by impressive roads cut into the cliffs. Grassy areas are used as pastures in the summer months, and the biannual migration (transhumance) of animals is a period of celebration for the people of Die.

The "Haut-Plateaux" (high plateaux) of the Vercors constitute the most high, most wild, and most protected part of the massif. There are no permanent residents, an absence of tarmacked roads, and no authorised access for motor vehicles. The sole economic activities are the forestry of woodland in accordance with the "garden forest" model, and the use of pastures for grazing in the summer.

Around the fringes of the massif, the Vercors regional park partially or totally covers an extra four distinct geographical areas:

The Royans, in the north-west, are an area of foothills devoted to the breeding and cultivation of walnuts. Three of the most impressive valleys descend to the edge of the Royans - the Gorges de la Bourne, the cirque of the Combe Laval, and the Échevis valley, including both the Grands and Petits Goulets.

The Gervanne, in the south-west, is a rugged area of hills at the foot of the plateau, with pretty villages. It is mainly orientated towards Crest.

The Diois is a part of the Drôme valley around Die. This region has a more markedly Mediterranean character, with vineyards and fields of lavender. It acts as a buffer between Gervanne and the interior of the massif, yet despite the relative ease of access to the latter, it tends to turn away from the plateau in favour of the valley.

The Trièves, in the east, is a low hilly plateau, situated between the highest summits of the Vercors and the gorge carved out by the Drac river. It is from the Trièves that the best views of Mont Aiguille can be obtained; it is also the most isolated part of the region.

Panoramic view of the main ridge of the massif, from the Moucherotte (on the left), to the Grande Moucherolle (on the right), as well as the val de Lans.

Principal summits[edit]

The crest of the Vercors on the left, opposing a single isolated summit
View of the Grand Veymont and Mont Aiguille from the south

From north to south:

Principal road cols[edit]

By altitude descending:

The tunnel du Mortier links Montaud with Autrans, at 1391 metres of altitude, but had to be closed after April 20 1992 following a landslide of 20,000 m3 of rock which involved part of the slope to the north of the route. The instability of the slopes have proved an impediment for the realisation of further work down from the site, particularly that which would benefit the road through the gorges d'Engins from Sassenage (the D531).

Geology[edit]

The constituent rocks of the Vercors were formed by sedimentation about 165 million years ago (mya), in the middle Jurassic period, at the bottom of the Piemont-Liguria Ocean. The deposition of animal material formed limestone, whilst detritus rocks formed primarily from the erosion of marl from the Variscan orogeny, in a period marked by changing climactic conditions and ocean depth. One layer, from the Tithonian, is characteristic of Diois and Trièves. Then, about 130 mya, in the Cretaceous, a rise in temperatures combined with shallow waters led to the development of coral reefs, which abounded with molluscs, particularly rudists, the origin of the urgonian limestone which forms the upper part of the massif, more prominently in the northern half. This primitive fauna left numerous fossils, for instance those found at site near Rencurel in the coulmes. In the Paleogene, the Tethys ocean closed up. At the start of the Miocene, the raising of the alps resulted in a nappe (thrust shift) to the west and rocks of sedimentary origin being raised 2,000 metres (6,600 ft) above the current location of the Massif des Écrins. The folding of these rocks resulted in the Vercors having local synclines and anticlines successively, and because of the hardness of the rock, faults. Subsequent marine transgressions were responsible for secondary sedimentation in the basins, following the widening of the gorges and erosion of the cliffs from runoff, leading to the formation of the Molasses in the Royans, but also in the valleys of Lans, Autrans, and Rencurel. At the close of the Miocene, a new period of uplifting brought about the final receding of the sea.

Once formed, the massif underwent severe erosion, which accentuated the relief. The different synclines grew larger, eventually forming valleys including those of Autrans—Méaudre and Lans—Villard—Corrençon as well as the Col de Romeyère and the Col de Rousset. The water hollowed out the cirque of Archiane, the Steephead valley of Bournillon, and the combe Laval.

Vercors in popular culture[edit]

The Vercors have appeared in many films, including;

See also[edit]

References[edit]

  1. ^ Les régions, Parc naturel régional du Vercors

Bibliography[edit]