Besòs (river)

The Besòs is a river in Catalonia, Spain. It originates in the Guilleries Massif and flows in a southerly direction for approximately 17 kilometers (11 miles) before emptying into the Mediterranean Sea near Sant Adrià de Besòs, just north of Barcelona.

The river's drainage basin covers a significant portion of the Vallès plain. Historically, the Besòs was heavily polluted due to industrial activity and urban runoff from the surrounding metropolitan area of Barcelona. The water quality was severely degraded for many decades.

Starting in the late 20th and early 21st centuries, significant efforts were undertaken to rehabilitate the Besòs. These included improvements in wastewater treatment, regulation of industrial discharges, and habitat restoration projects along its banks. As a result, the river's ecological health has improved substantially, with a return of certain fish species and increased biodiversity.

The area surrounding the mouth of the Besòs has been transformed into a recreational space, featuring parks, beaches, and cycling paths. The river now plays a crucial role in the urban landscape of the Barcelona metropolitan area, providing both environmental and recreational benefits.