Grijalva River, formerly known as Tabasco River. (Spanish: Río Grijalva, known locally also as Río Chiapa and Mezcalapa River) is a 480 km (300 mi) long river in southeastern Mexico. It is named after Juan de Grijalva who visited the area in 1518. The river rises in Chiapas highlands and flows from Chiapas to the state of Tabasco through the Sumidero Canyon into the Bay of Campeche. The river's drainage basin is 134,400 km2 (51,900 sq mi) in size. Because of the close connection to the Usumacinta River (the two combine, flowing into the Gulf of Mexico in a single delta), they are often regarded as a single river basin, the Grijalva-Usumacinta River.