The Caristales River, located near La Macarena in Columbia, South America is famous for its colorful display and has been called "the river that ran away to paradise", "the most beautiful river in the world" and "the river of five colors".
During Colombia 's wet season, the water flows fast and deep, obscuring the bottom of the river and denying the mosses and algae the sun that they need; and during the dry season there is not enough water to support the dazzling array of life in the river, but during a brief span between the wet and dry seasons, when the water level is just right, the many varieties of algae and moss bloom in a dazzling display of colors. Blotches of amarillo , blue, green, black, and red - and a thousand shades in between - coat the river. The part of the river where the colorful blooms occur is quite isolated and is not accessible by road. Adventurous tourists can now fly into La Macarena and then make their way to to the river site on foot as part of guided tours. The site was effectively closed to tourists for several years because of guerrilla activity in the region along with concerns about the impact of unregulated tourist traffic. However, the site was reopened to visitors in 2009.
So far, some 1,000 people have visited Caristales, including around 100 foreign tourists.