The Río Tinto is a river in southwestern Spain that originates in the Sierra Morena mountains of Andalusia. Since ancient times, a site along the river has been mined for copper, silver, gold, and other minerals.As a result of the mining, Río Tinto is notable for being very acidic (pH 2) and its deep reddish hue is due to iron dissolved in the water. Acid mine drainage from the mines leads to severe environmental problems due to the heavy metal concentrations in the river.
