The course of the Adour was changed in 1578 by dredging under the direction of Louis de Foix, and the river returned to its former mouth. Bayonne flourished after regaining the maritime trade that it had lost for more than a hundred years.
The Adour River's course was modified in 1578 by dredging overseen by Louis de Foix, leading to a return to its original mouth. This change facilitated Bayonne's economic recovery as it regained access to maritime trade after a prolonged absence.