River, southeastern Mexico.
Its headstreams rise in the Sierra Madre of Guatemala and the Sierra de Soconusco of Mexico. It flows northwest through Chiapas state (where it is known locally as the Chiapa River) and then roughly parallels the border of Chiapas and Tabasco states. The river turns northward at Villahermosa and empties into the Bay of Campeche after some 400 mi (640 km). It is navigable by shallow-draft vessels for about 60 mi (95 km) upstream from its mouth and for several stretches along its middle and upper course.