The Arcachon Basin is part of the “County of Buch” which is located in the heart of the Landes de Gascogne, half-way between Pointe de Grave and Capbreton, in the south-west portion of the Gironde département, and about 50 kilometres (30 miles) from Bordeaux.
Around the edges there are about 80 kilometres (50 miles) of flat coastline or dunes and woodland. This begins at Pyla sur Mer then runs northwards to Arcachon, turns to the east and then south, and then eastwards again near La Teste de Buch. The coast then moves north-west incorporating the delta of the River Leyre, then from Lège, begins to run south-west down to Cap-Ferret, opposite Pyla sur Mer. In the middle lies “l’île aux oiseaux” (bird island) with its stilted huts.