Arros (river)

The Arros is a river in southwestern France that flows through the Hautes-Pyrénées and Gers departments, in the Occitanie region. The Arros is a right tributary of the Adour river.
The valleys of the Arros and of the Adour rivers were part of the "Comté de Bigorre" ("County of Bigorre"). The valley of the Arros was called the "Rivière-Haute" ("Upper River") and the valley of the Adour was called the "Rivière-Basse" ("Lower River").
Geography.
The Arros river has a length of , and a drainage basin with an area of approximately .
Its average yearly discharge (volume of water which passes through a section of the river per unit of time) is at Juillac in the Gers department.
Course.
The Arros river starts, an altitude of , in the "Forêt des Baronnies", southeast of Bagnères-de-Bigorre, in the Esparros "commune". It then flows from south to north through the Hautes-Pyrénées department. It passes through the towns of Bourg-de-Bigorre, Tournay and Chelle-Debat. It gets in the Gers department and passes through the towns of Montégut-Arros and Villecomtal-sur-Arros.
About from Plaisance, the Arros joins, by its right side, the Adour river at an altitude of .
The Arros flows through 55 "communes" and two of them, both in the Gers department, have the name of the river: Montégut-Arros and Villecomtal-sur-Arros.
Main tributaries.
Most of the tributaries of the Arros are small streams; the only important tributaries are:
Left tributary:
Right tributary: