Cano Cristales River in Colombia, also known as the "River of Five Colors" or "Rainbow River", transforms into a spectacular natural display of colors for a brief period each year due to special algae that grow on the riverbed rocks. During this time between wet and dry seasons, the entire riverbed is covered in an array of blues, greens, reds, and other hues. This colorful phenomenon only lasts a few days when conditions are optimal for the algae before the river either floods or dries up. The remote river is only accessible by horse or mule on occasional tours.