The Papaloapan River (Spanish: Río Papaloapan) is one of the main rivers of the Mexican state of Veracruz. Its name comes from the Nahuatl papaloapan meaning river of the butterflies.
The Papaloapan rises in the Sierra Madre de Oaxaca on the border between the states of Veracruz and Oaxaca. It is formed where the Santo Domingo River and the Valle Nacional River join to the southwest of San Juan Bautista Tuxtepec in Oaxaca.The Tonto River is another major tributary.
The Papaloapan meanders for 122 km (76 mi) in a northeasterly direction through the coastal plain before draining into Alvarado Lagoon. The river basin covers 46,517 km2 (17,960 sq mi), the second largest in Mexico, and contains 244 municipalities with a population of about 3.3 million people. The cities of San Juan Bautista Tuxtepec and Tlacotalpan (Veracruz) are situated on the banks of the Papaloapan.
