Garonne Basin

Description

Flowing for a distance of 525 km, the Garonne is the most important river of Southwestern France. Its watershed covers 57 000 km2. It originates in Spain at 1 900 m altitude in the Val d’Aran in the Pyrénées. Its main tributaries are the Lot, the Tarn and the Aveyron. After the city of Toulouse, the Garonne becomes navigable. It goes through Bordeaux and joins the Dordogne to form the Gironde estuary. The Gironde estuary is the largest estuary in Europe: 75 km long, up to 12 km wide, covering an area of 635 km².