The Cano Cristales, or ‘River of Five Colors,’ in Sierra de la Macarena, Colombia, literally blooms at the end of the rainy season. When both the water level and current decreases, an endemic aquatic plant called Macarenia Clavigera fills the river with a deep pink hue which protects the plant from solar radiation. The river is also home to numerous cavities formed out of Precambrian rocks by the deposit of sediments that naturally carve the pits bigger and bigger as the water swirls the pebbles around. Many call “The Liquid Rainbow” the most beautiful river in the world because of the varied and striking colors found in its waters. These beautiful pictures were taken by nature photographer Olivier Grunewald.