Nature is often full of mysteries and surprising phenomena. Ice-covered lighthouses, astonishingly-shaped clouds, but also changing rivers... like the one in Yorkshire that turned orange, surprising everyone in the region. And this isn't the first time something like this has happened!Located in the Serrania de la Macarena, which has nothing to do with the eponymous song and dance, in the center of Colombia, the Caño Cristales, a river, sometimes displays many colours at the same time, creating a sublime result.A show visible only a few months a yearYellow, blue, red, black and green, these are the colours that decorate this river during the beautiful days between June and November, after the rainy season in Colombia. The river turns into a rainbow, which is also one of its other nicknames, which makes it the most beautiful river in the world.It's hard to believe, but it's real. But how can this river spanning over a hundred kilometres have these five colours imprinted upon it? Simply thanks to the endemic algae found at the bottom of the river, called Clavigera Macarenia, a small red plant. It is therefore a perfectly explainable scientific phenomenon, and not some kind of magic, even though it does remind us of a fairytale landscape.Check out the video above to see this stunning phenomenon for yourself!