Rio Tinto, Huelva, Spain (© David Santiago Garcia/Aurora Photos)

【September 9 2014】From its source in the Sierra Morena mountains, Spain’s Rio Tinto runs red. The coloration results primarily from iron ore dissolved in the water. However, there are many other trace minerals in the water, possibly due to copper, gold, and silver mining in the banks and hills nearby.Explore breathtaking Gallery from the HuluTrip homepage over the past 5 years..