It is 402 kilometers long and is the largest in Campeche. It is characterized by its large number of falls, among which the Salto Muerto, Salto Grande and Salto Toro stand out.
It originates in Guatemala, in el Petén, and crosses the border between the two countries. It empties into the Laguna de Panlao which is connected to the Laguna de Términos.
It is navigable for almost all its length and is perfect for the practice of aquatic sports.