The Adour is a river in southwestern France. It rises in High-Bigorre (Pyrenees), in the commune of Aspin-Aure, and flows into the Atlantic Ocean near Bayonne. It is 308.3 kilometres (191.6 mi) long, of which the uppermost ca. 11 kilometres (6.8 mi) is known as the Adour de Payolle. At its final stretch, i.e. on its way through Bayonne and a short extent upstream, the river draws the border between the Northern Basque Country and Landes regions.