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Dune of Pyla
Highest point
Elevation	106.6
Coordinates	44°35′23″N 1°12′49″W
Geography
Location	Gironde
Country	France
Région	Nouvelle-Aquitaine
Geology
Age of rock	about 200 years
Mountain type	Dune
Type of rock	Sand
Climbing
Easiest route	Many roads are available

Dune of Pyla

Must not be confused with Pilat (massif montagneux), Pilate, Pilates (sport) ou Pilatte (refuge).

The dune of Pyla is situated on the border of the massive forest Landes de Gascogne on the “côte d’argent” in the entry of the “bassin d’arcachon” in france and is the highest dune in Europe (height in 2018 : 106,6 m2)

Sommaire

• 1 Geography
  • 1.1 Localisation
  • 1.2 Topography
  • 1.3 Geology
  • 1.4 Sedimentology of the sands of the Landes and dunes
• 2 History
• 3 Formation
• 4 Tourisme and preservation
• 5 Public transport
• 6 Culture
• 7 References
• 8 See also
  • 8.1 Bibliography
  • 8.2 Related articles
  • 8.3 external links

Geography

Localisation

Located at the southern entrance to the Arcachon Basin, it stretches 616 m from west to east and 2.9 km from north to south and contains about 550 million cubic meters of sand in the town of Pyla-sur-Mer which administratively depends on the municipality of La Teste-de-Buch, near Arcachon, in the heart of the Landes de Gascogne.

Topography

The movements of the dune are constant and studied by scientists. On the east side, the dune gains on the forest, deforestating trees at a speed of one to five meters per year. On the West side, the evolution of the coastline (limit of the highest seas) is variable. The northern coast of the dune is subject to severe erosion, especially during winter storms. Conversely, erosion has been low or almost null in recent years along the southern coastline. The dune of Pyla is asymmetrical, with a slope inclined differently according to its position relative to the wind. Thus, the face of the dune most exposed to the wind (west face, ocean side) is soft, of the order of 5 to 20 °, because the sands spread during their ascent to the summit. In contrast, the forest side, sheltered from the wind (east face), is steeper, between 30 and 40 °.

Geology

On the geological map of the western part of the Aquitaine Basin and of La Teste-de-Buch, in particular, we can see a late Quaternary geological formation called "Sable des Landes": it covers the entire area around the basin of Arcachon and spread north to the entry of the Gironde, east to the Garonne valley and south to Armagnac and Adour. To the west, it is surmounted by a strip of newer coastal dunes including the dune of Pyla.

Sedimentology of the sands of the Landes and dunes

Rescue search on a protohistoric site (October 2014) by Philippe Jacques with samples in a thick layer of compacted peat.

The sand cover of the Landes is composed of:

• On the lower part, a layer of sand, gravel or even pebbles, clays with a texture that is sometimes sandy and more or less gravelly, whose thickness reaches 100 meters near the coastline and which is decreasing towards the continental reliefs that it covers more or less; these sediments have been spread by rivers and streams; they have a fluviatile origin;
• On the upper part, a few meters of fine sand composed of blunted and frosted grains, because of the wind, which constitutes the true "Sable des Landes" and which comes from the reworking of the fluvial sediments that it overcomes.

All the relief of the coastal zone was covered by this sand which was put in place under very arid conditions, pushed by prevailing westerly winds from 20000 to 10000 BC. J.-C. The heaviest fraction, the gravels, remained near the shore off the present coast, while the finest fractions were carried very far to Blaye, Entre-deux-Mers and Chalosse. It is a very homogeneous sand (90% of the grains have a size between 0.1 and 0.5 mm, the average grain diameter is 0.3 mm). This homogeneity results come from the sorting done by the waters and the winds.

In addition to quartz grains, there are minerals in these sands whose density is greater they’re called heavy minerals; they represent 0.2 to 1.5% of the sand and are composed of iron-bearing minerals (75%) but also tourmaline and garnets. They exist in all the sands of the region as well in the soil of the Landes.

The region of the Arcachon basin and the ponds to the south, Cazaux, Parentis, caught the attention of geologists who were looking for oil in this area who were a long time ago covered by the seas of the secondary era. This work has resulted in a better geological understanding of these lands deeply buried under the Tertiary sediments and the thick layer of sand that was established in the late Quaternary. In addition, the low sandy coasts of the Gironde and the Landes, where erosion happen, sediment transport and accumulation form the three inseparable stages of shoreline evolution and dune systems, proved to be a model of choice that many regional geologists are interested in today. The history of the dunes in this region, and Pilat in particular, is a natural part of these studies.

History

The entry of the Havre d'Arcasson in 1731

The current location of the Dune of Pyla is temporary in the protohistoric settlements, for activities related to the exploitation of sea salt. The first archaeological discoveries began in 1982. On December 31, 2013, a tourist found in the sand, at the foot of the dune, a funeral urn and an accessory vase dating from the Iron Age, 800 BC. AD

An excavation site mobilized a dozen amateur archaeologists for two weeks, in October 2014, to clarify the stratigraphic and environmental context of the reported discoveries. A photo report is available on the site of the Historical and Archaeological Society of the Arcachon Basin.

The name Pyla, already present on the maps of Mass (1708) and Cassini (1786) with the "small pond of Pyla", the "beacons of Pyla", "huts of Pyla" and the "great pass of Pyla or from the south ", corresponded to a location further south than the current dune and presumably off the present coast. In fact, the coastal dunes move inland as the coastline recedes. Until the beginning of the twentieth century, the Pilat sector is called "Sabloneys" (literally "sablières" in Gascon); no road can lead to it.

This change of name comes from a real estate transaction. When, around 1910, the development of the habitat operated on the coastal part of the commune of Arcachon reached the south of Moulleau, the real estate developers who covet land on the testine part which prolongs the coast towards the south, are confronted with a big problem: the territory belongs to the state that does not want to sell. In 1913, one of these promoters, Daniel Meller, then proposes and obtains from the administration a transaction: in exchange for 463 hectares of land that he buys on the commune of La Teste (on the banks of the lake of Cazaux), he gets 143 hectares between Le Moulleau and the dune of Pyla. He chose to name the place "Pyla-sur-Mer" in reference to the dune but giving this place name a Greek connotation, very fashionable at the time. He created the "Société Civile Immobilière de Pyla-sur-Mer" in order to erect "a city in the forest".

It was around 1930 that the old name "Sabloney" was replaced by "dune du Pyla". Today, "Sabloneys" means a small beach south of the Great Dune.

The official name of the dune is "Dune of Pyla". This name comes from a Gascon derivative of Latin pīla meaning heap, mound.

Formation

The formation of the dune is entirely linked to the Banc d'Arguin. Over the centuries, the sea currents have carried sand (from the open sea, the coast, and the basin when the tide goes down) to form the Banc d'Arguin (which is, like the dune, in constant evolution). Then, the strong westerly winds coming from the sea, with the help of micro droplets of water, tear at the surface sands at the bench of Arguin at the time of the low tide, when it is totally discovered, and and fly away to rest on the dune to form this gigantic mass of fine sand.

On the western slope of the dune, there are four major paleosols (ancient fossilized soils): at the base of the dune, an ancient podzol (3500 BC), then three main dune paleosols (dated between 3000 BC years BC and now). There are also minor paleosols, lake levels, and several thousand heavy mineral levels.

There was first, after the last ice age, a forest of Scots pine, hazel, birch, alder and willow, characteristic of a cold and continental climate. In the boreal Atlantic and sub-boreal, a dune three to four meters high, held marshes and a pond; Throughout the Flandrian transgression, the sands accumulated and the marshes disappeared under the parabolic dunes from twenty to forty meters high, while the forest of La Teste developed under a wetter climate.

In the seventeenth and eighteenth centuries, with the massive arrival of sand on the coast, the modern dunes buried, under fifty to sixty meters of sand, the old parabolic dunes, to become the great "dune of the Grave". The sand continued to arrive and converge towards the dune of Grave. At the end of the nineteenth century, the Grave dune is consisted of 20 to 30 m of sand, reaches 115 m around 1910 and takes the name of dune of Pyla. The Great Dune of Pilat was built between 1826 and 1922 while the coastline retreated more than 500 m. The vegetation that covered the slope to the wind of the dune of Grave was destroyed, allowing the winnowing and the transport of the sands towards the top of the dune.

Tourisme et Preservation

The edge of the Pyla dune beach side. April 2018.

The notoriety of the highest dune in Europe has only grown in recent decades. Nearly two million visitors climb each year to its summit, making it one of the most visited natural sites in France with the bay of Mont-Saint-Michel.

It is nonetheless a fragile natural area. It is the subject of a preservation and enhancement program carried by public actors, including the site manager, “le Syndicat mixte de la Grande Dune du Pilat”..

More than 6,800 hectares including the dune and adjoining forest are classified under the May 1930 Act on Natural Monuments and Sites. The ranking is a strong protection at the national level. The Syndicat mixte is a member of the Réseau des Grands Sites de France. This network accompanies its members towards the Grand Site de France label.

Parapentes au-dessus la dune.

Outdoor sports are present on the site including paragliding. Paid parking, contributing to the preservation of the classified site, is located at the foot of the dune, forest side. Access to the Pyla Dune remains free for pedestrians, bicycles and public transport such as the Baïa bus.

According to a study published at the end of 2014, the Dune du Pilat would generate between 11 and 13 million euros in direct benefits, and up to 168 million euros in indirect revenue.

Public transport

•  1  Gare d’Arcachon ↔ Dune du Pilat ↔ Plage de la Salie
  • Arrêt : Dune du Pilat
•  2  Gare de la Teste ↔ Dune du Pilat ↔ Plage de la Salie
  • Arrêt : Dune du Pilat
•  6  Port du Teich ↔ Plage de la Salie (fonctionne entre juin et septembre)
  • Arrêt : Dune du Pilat

Réseau exploité par la RDTL, transports en commun du département des Landes.

• 46  Parentis ↔ Biscarrosse ↔ Arcachon (fonctionne entre juin et septembre)
  • Arrêt : Dune du Pilat

Culture

In 2018, the mixed group released a piece called The Dune of Pilat whose clip is shot on the dune.