From Saint-Jean-de-Marsacq, the route winds along the banks of the Adour, lined with flood-prone wet meadows known as ‘barthes’ and designated as a Natura 2000 site. These are home to remarkable species such as the otter and the European pond turtle, a small freshwater turtle.

Urt, a former fishing village with a distinctly Basque atmosphere, featuring a pelota court and a white church, was Roland Barthes’ adopted home.