Rio Tinto, Spain
Spain’s bright red Rio Tinto is a spectacular sight as it flows from the Sierra Morena mountains — colouring the surrounding landscape as it passes. Visitors are drawn here to see its eye-catching colours, but those thinking about swimming in the vibrant waters should think again.
The Rio Tinto is extremely acidic, with a pH as low as 1.7, so a dip here would be hazardous! The Rio Tinto’s chemical nature is the result of extreme mining pollution, with heavy metals — including gold, silver and copper — present in the water in significant proportions. The result is a harsh environment that isn’t conducive to life.
There isn’t much living here, and those venturing in will be putting their health at risk. Dangerous bacteria thrives under such conditions and, whilst the river can be pleasant to look at, bathing should be avoided. Do take a look, but don’t take a dip.