The Guadiamar is a river of Andalusia, Spain, and a tributary of the Guadalquivir.
It flows through Doñana National Park.
In 1998, the company Boliden AB was responsible for a major ecological disaster in Spain, when a reservoir of toxic waste in the town of Aznalcóllar, owned by its subsidiary Boliden-Apirsa, broke and spilled its contents in the course of the Guadiamar river.
Coordinates: 36°54′12″N 6°20′05″W / 36.90333°N 6.33472°W