A famous river in Spain that flows with reddish water continues to have historical and scientific significance.
The Rio Tinto is often noted as the site where the Copper Age and Bronze Ages likely began with the first mines in the area being established around 3000BC.
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Stories about the valuable gold and silver being found there attracted various groups throughout history including the Romans and the Moors.
In fact it's the iron from these activities that has turned the river its signature reddish colour.
Despite the fact that the water has become dangerously acidic for humans, it attracts biologists because a number of unusual microbes have been found living there.
For astronomers Rio Tinto is considered to be an analogue for Mars and data from NASA has indeed indicated some overlaps between the two environments.
The general theory is that if life can exist in this highly metallic and acidic river it might also be present in the similarly harsh conditions of other bodies in our solar system.