Caño Cristales is a river in Columbia located in the Serrania de la Macarena province of Meta and is commonly called the River of Five Colours or the Liquid Rainbow, because its waters contain all of the colours of the rainbow thanks to marine plants known as macarenias on the riverbed. The ideal time to visit the Sierra de La Macarena National Natural Park is between July and November, which is accessible via plane from Villavicencio and Bogota. The park has an area of 630,000 hectares.