The Río Pantaleón is a river in the south of Guatemala. Its sources are located in the Sierra Madre

Sierra Madre de Chiapas

Sierra Madre is a mountain range which runs northwest-southeast from the state of Chiapas in Mexico across Guatemala and into El Salvador and Honduras. Most of the volcanoes of Guatemala are a part of this range.A narrow coastal plain lies south the range, between the Sierra Madre and the Pacific...

 range, on the western slopes of the Volcán de Fuego

Volcán de Fuego

Volcán de Fuego is an active stratovolcano in Guatemala. It is close to the city of Antigua Guatemala. It has erupted frequently since the Spanish conquest. "Fuego" is famous for being almost constantly active at a low level. Smoke issues from its top daily, but larger eruptions are rare. On...

 in the departments of Chimaltenango

Chimaltenango (department)

Chimaltenango is a department of Guatemala. The capital is Chimaltenango. Located to the east are the departments of Guatemala, home to Guatemala City, and Sacatepéquez, while also bordered by the departments of El Quiché and Baja Verapaz to the north, Escuintla and Suchitepéquez to the south, and...

 and Escuintla

Escuintla (department)

Escuintla is one of the 22 departments of Guatemala. Its capital is the city of Escuintla. The department of Escuintla covers an area of 4,384 km² and is situated in the coastal lowland region to the South of Guatemala-City, bordered by the Pacific Ocean. Escuintla produces about 43 percent of...

. The river flows in a south-westerly direction through the coastal lowlands of Escuintla where it joins the San Crostobal River, a tributary of the Coyolate River

Coyolate River

The Río Coyolate is a river in southwest Guatemala. Its sources are located in the Sierra Madre range, in the department of Chimaltenango. It flows southwards through the coastal lowlands of Suchitepéquez and Escuintla to the Pacific Ocean....

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The Pantaleón river's proximity to the active Fuego volcano increases the risks of inundations and mudflows.