ENGINEERING BEHIND THE COLOR OF RED RIVER

The stunning Red River in Cusco is just one more example of the mind-blowing scenery of the Peru. This peculiar waterway runs red for about 5 kilometers before combining with some other area streams and small rivers, at which point the color becomes more diluted and loses its unique hue. At last, it will get combined with the mighty AMAZON River.

Cusco’s Red River is formed due to rain run-off from the nearby Palcoyo Rainbow Mountain. The range of colors in this vibrant valley are a result of the different mineral content on different layers of soil, which have been made visible by erosion. The Red River’s coloring is the result of red sandstone full of iron oxide. This mineral-rich sedimentary rock gets washed off the hillsides when it rains and turns the water a distinct red or pink hue (the exact tone depends on the volume of precipitation). Because it is a result of rain run-off, this red or pink river in Cusco is typically only visible during Peru’s rainy season months. During the rest of the year, the river’s water level is much lower and its color is a more typical muddy-brown hue.