It's a biological wonder known as the " river of five colors ." Some say Caño Cristales is "the most beautiful river in the world."
In reality, for most of the year, Caño Cristales is indistinguishable from many other rivers, appearing like a bed of mossy rocks covered in crystalline water.
There are moments, however, when the river is tinged with many vibrant colors: between the wet and dry seasons, when the water level is favorable, a unique species of plant on the riverbed turns a brilliant red. This is Macarenia clavigera , whose color blends with the yellow and green sand, the blue water, and all the shades in between.
During Colombia's rainy season, the water flows too fast and becomes too deep, darkening the riverbed and preventing the plants from accessing the sun needed to turn red. In the dry season, however, there isn't enough water. But from September to November, the river becomes a "liquid rainbow." Witnessing this spectacle isn't easy, as it's located in an isolated area with no roads. Adventurous tourists, however, can land in the town of La Macarena , and from there it's just a short drive to Serrania de la Macarena, the national park that hosts the river.