Arcachon Basin or alternatively Arcachon Bay ( French: ''Bassin d'Arcachon'') is a bay of the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

on the southwest coast of

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

, situated in Pays de Buch between the

Côte d'Argent Côte d’Argent (; ) is a name given to part of the Atlantic coast of the Aquitaine region in France. Etymology The term was first coined to describe the Aquitaine coast in 1905 by the journalist and poet Maurice Martin. The Congrès national d ...

and the Côte des Landes, in the region of

Aquitaine Aquitaine ( , , ; oc, Aquitània ; eu, Akitania; Poitevin-Saintongeais: ''Aguiéne''), archaic Guyenne or Guienne ( oc, Guiana), is a historical region of southwestern France and a former administrative region of the country. Since 1 Janu ...

. The bay covers an area of at high

tide Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables ...

and at low tide. Some of its geological features are natural preservation areas.Nicola Williams, Oliver Berry, Stuart Butler, Jean-Bernard Carillet, Kerry Christiani, Gregor Clark, Emilie Filou, Catherine Le Nevez & Daniel Robinson (2015). Lonely Planet France (Travel Guide) Paperback – 13 Mar 2015 by Lonely Planet. The general shape of the Bassin d'Arcachon is that of an equilateral triangle pointing north, the southwest corner of which is open to the sea, between

Cap Ferret Cap Ferret (English: ''Cape Ferret'') is a headland, situated at the south end of the ''commune'' of Lège-Cap-Ferret in the French ''department'' of Gironde and ''region'' of Nouvelle-Aquitaine. The headland takes the form of a spit, which sepa ...

and the town of

Arcachon Arcachon ( ; ) is a commune in the southwestern French department of Gironde. It is a popular seaside resort on the Atlantic coast southwest of Bordeaux, in the Landes forest. It has a sandy beach and a mild climate said to be favourable for i ...

(more specifically, one of the suburbs of La Teste-de-Buch, Pyla-sur-Mer), through a narrow channel (Les Passes). On the north shore is the town of Arès, then Andernos-les-Bains on the northeast. Just south of the entrance is the

Dune of Pilat The Dune of Pilat (French: ''Dune du Pilat'', official name), also called ''Grande Dune du Pilat'', is the tallest sand dune in Europe. It is located in La Teste-de-Buch in the Arcachon Bay area, France, 60 km (37.2 mi) southwest of Bor ...

. Nearly in the middle of the bay is a very particular island: L'île aux Oiseaux (Isle of the Birds).

Development

In the past, similar areas became lakes (called in French ''lacs'' or ''étangs'') and are nowadays filled with fresh water. On the French Atlantic coast, running north–south between the Gironde estuary to the

Adour River The Adour (; eu, Aturri; oc, Ador) is a river in southwestern France. It rises in High- Bigorre (Pyrenees), in the commune of Aspin-Aure, and flows into the Atlantic Ocean ( Bay of Biscay) near Bayonne. It is long, of which the uppermost ca. ...

mouth, are the

Lac d'Hourtin-Carcans The Hourtin-Carcans Lake (french: lac d'Hourtin-Carcans, ; oc, lac de Hortin e de Carcan) is a lake in the natural region of Médoc, located in the French department of Gironde, Aquitaine. It is one of the largest lakes in France, and the larges ...

, the Lac de Lacanau, the

Étang de Cazaux et de Sanguinet Étang de Cazaux et de Sanguinet is a lake in Gironde / Landes, France. At an elevation of 12 m, its surface area is 55 km². The lake was formed due to the river Gorgue and the sand dunes on the coast which blocked the river thousands of y ...

, the Étang de

Biscarrosse Biscarrosse (; oc, Biscarròssa) is a commune in the Landes department in Nouvelle-Aquitaine in southwestern France. It is located southwest of Bordeaux, and inland from the seaside resort of Biscarrosse-Plage on the Atlantic coast. Near Bis ...

et de Parentis, the Étang d'Aureilhan, the Étang de Léon, the Étang de Soustons, Étang Hardy, Étang Blanc and the Étang de Garros. Arcachon Bay is the last water area that remains open to the ocean. The Bassin still has a link to the sea perhaps because of the Eyre River that runs from the

Landes forest The Landes forest (; La forêt des Landes in French) in the Landes de Gascogne (las Lanas de Gasconha in the Gascon language), in the historic Gascony natural region of southwestern France now known as Aquitaine, is the largest man-made woodland ...

and has its mouth (Delta de l'Eyre) in its southeast corner. Otherwise the Bassin would have become blocked by the

sandbanks Sandbanks is an affluent neighbourhood of Poole, Dorset, on the south coast of England, situated on a narrow spit of around 1 km2 or 0.39 sq mi extending into the mouth of Poole Harbour. It is known for its high property prices and for it ...

built up by the tides. Bassin d'Arcachon - Cabanes tchanquées.jpg, ''Cabanes tchanquées'' on the ''Isle of Birds'', near Arcachon CarteBassinArcachon.png, Map of the ''Bassin d'Arcachon'' FormationBassinArcachon.png, Formation of the ''Bassin d'Arcachon'' at 4000 BC, 400 BC, 700 AD, 1300 AD, 1708 AD and today. Green areas are mud and sand bars. Beige areas are sand dunes.

References

{{Authority control Landforms of Gironde Bays of Metropolitan France Ramsar sites in Metropolitan France