Marañón River

Last updated
Marañón River
Valley of the Marañón between Chachapoyas (Leimebamba) and Celendín
Map of the Amazon Basin with the Marañón River highlighted
Country Peru
Physical characteristics
Source Andes
Mouth Amazon River
Length1,737 km (1,079 mi)
Basin size358,000 km2 (138,000 sq mi)
  average16,708 m3/s (590,000 cu ft/s)
Basin features
  left Tigre, Cunincu, Urituyacu, Nucuray, Ungumayo, Pastaza, Sasipahua, Morona, Cangaza, Santiago, Cenepa, Chinchepe, Choros, Linlín, Artesamayo, Choropampa, Madgalena, Cortegana, Chipche, Mireles, Chusgón, San Sebastián, Casga, Mamara, Mayas, Actuy, Rupac, Yanamayo, Puchca, Contan, Vizcarra
  right Yanayacu, Huallaga, Cahuapanas, Potro, Apaga, Saramiriza, Nieva, Cananya, Chiriaco, Congón, Rumirumi, Shuve, Chumuch, Pusac, Lavasen, Gansul, San Miguel, Challas River, Tantamayo, San Juan

The Marañón River (Spanish : Río Marañón, IPA:  [ˈri.o maɾaˈɲon] ) is the principal or mainstem source of the Amazon River, arising about 160 km to the northeast of Lima, Peru, and flowing through a deeply eroded Andean valley in a northwesterly direction, along the eastern base of the Cordillera of the Andes, as far as 5° 36′ southern latitude; from where it makes a great bend to the northeast, and cuts through the jungle Andes, until at the Pongo de Manseriche it flows into the flat Amazon basin. [1] Although historically, the term "Marañon River" often was applied to the river all the way to the Atlantic Ocean, nowadays the Marañon River is generally thought to end at the confluence with the Ucayali River, after which most cartographers label the ensuing waterway the Amazon River.



The Marañón River is Peru’s second-longest river according to a 2005 statistical publication by the Instituto Nacional de Estadística e Informática. [2] :21, pdf 13

Source of the Amazon

The Marañon River was considered the source of the Amazon River starting with the 1707 map published by Padre Samuel Fritz, [3] :58 who indicated the great river “has its source on the southern shore of a lake that is called Lauricocha, near Huánuco." Fritz's reasoning was based on the fact that the Marañon River is the largest river branch one encounters when journeying upstream, something clearly evident on his map. For most of the 18th–19th centuries and into the 20th century, the Marañon River was generally considered the source of the Amazon. The Marañon River continues to claim the title of the "mainstem source" or "hydrological source" of the Amazon due to its contribution of the highest annual discharge rates.


The initial section of the Marañon contains a plethora of pongos, which are gorges in the jungle areas often with difficult rapids.[ citation needed ] The Pongo de Manseriche is the final pongo on the Marañon located just before the river enters the flat Amazon basin. It is 5 km (3.1 mi) long and located between the confluence with the Rio Santiago and the village of Borja. According to Captain Carbajal, who attempted ascent through the Pongo de Manseriche in the little steamer Napo, in 1868, it is a vast rent in the Andes about 600 m (2000 ft) deep, narrowing in places to a width of only 30 m (100 ft), the precipices "seeming to close in at the top." Through this canyon, the Marañón leaps along, at times, at the rate of 20 km/h (12 mi/h). [1] The pongo is known for wrecking many ships and many drownings.

Downstream of the Pongo de Manseriche, the river often has islands, and usually nothing is visible from its low banks, but an immense forest-covered plain [1] known as the selva baja (low jungle) or Peruvian Amazonia. It is home to indigenous peoples such as the Urarina of the Chambira Basin , the Candoshi, and the Cocama-Cocamilla peoples.

A 552-km (343-mi) section of the Marañon River between Puente Copuma (Puchka confluence) and Corral Quemado is a class IV raftable river that is similar in many ways to the Grand Canyon of the United States, and has been labeled the "Grand Canyon of the Amazon".[ citation needed ] Most of this section of the river is in a canyon that is up to 3000 m deep on both sides – over twice the depth of the Colorado's Grand Canyon. It is in dry, desert-like terrain, much of which receives only 250–350 mm/rain per year (10–14 in/yr) with parts such as from Balsas to Jaén known as the hottest infierno area of Peru. The Marañon Grand Canyon section flows by the village of Calemar, where Peruvian writer Ciro Alegría based one of his most important novels, La serpiente de oro (1935).

Historical journeys

La Condamine, 1743

One of the first popular descents of the Marañon River occurred in 1743, when Frenchman Charles Marie de La Condamine journeyed from the Chinchipe confluence all the way to the Atlantic Ocean. La Condamine did not descend the initial section of the Marañon by boat due to the pongos. From where he began his boating descent at the Chiriaco confluence, La Condamine still had to confront several pongos, including the Pongo de Huaracayo (or Guaracayo) and the Pongo de Manseriche.

The Grand Canyon of the Amazon

Maranon River as seen from Quchapata in Peru Precipicio Rio Maranon alargado.jpg
Marañon River as seen from Quchapata in Peru

The upper Marañon River has seen a number of descents. An attempt to paddle the river was made by Herbert Rittlinger in 1936.[ citation needed ] [4] Sebastian Snow was an adventurer who journeyed down most of the river by trekking to Chiriaco River starting at the source near Lake Niñacocha. [5] [ page needed ]

In 1976 and/or 1977, Laszlo Berty descended the section from Chagual to the jungle in raft. [6] In 1977, a group composed of Tom Fisher, Steve Gaskill, Ellen Toll, and John Wasson spent over a month descending the river from Rondos to Nazareth with kayaks and a raft. [7] In 2004, Tim Biggs and companions kayaked the entire river from the Nupe River to Iquitos. [8] In 2012, Rocky Contos descended the entire river with various companions along the way. [9]

Hydroelectric dams

The Marañon River may supply 20 hydroelectric megadams planned in the Andes, and most of the power is thought to be destined for export to Brazil, Chile, or Ecuador. [10] Dam survey crews have drafted construction blueprints, and the environmental impact statements have been available since November 2009 for the Veracruz dam, [11] and since November 2011, the Chadin2 dam. [12] [13] A 2011 law stated "national demand" for the hydroelectric energy, while in 2013, Peruvian President Ollanta Humala explicitly made a connection with mining; the energy is to supply mines in the Cajamarca Region, La Libertad, Ancash Region, and Piura Region. [14] Construction of the 406 MW dam in Chaglla District started in 2012. [15]


Opposition arose because the dams are expected to disrupt the major source of the Amazon, alter normal silt deposition into the lower river, damage habitat and migration patterns for fish and other aquatic life, displace thousands of residents along the river, and damage a national treasure "at least as nice as the Grand Canyon in the USA". Residents have launched efforts to halt the dams along the river with conservation groups such as SierraRios [16] [17] and International Rivers. [18]

Potential ecological impacts of 151 new dams greater than 2 MW on five of the six major Andean tributaries of the Amazon over the next 20 years are estimated to be high, including the first major break in connectivity between Andean headwaters and lowland Amazon and deforestation due to infrastructure. [19]

See also

Related Research Articles

Amazon River Major river in South America

The Amazon River in South America is the largest river by discharge volume of water in the world, and the disputed second longest river in the world.

Madeira River River in Bolivia and Brazil

The Madeira River is a major waterway in South America. It is estimated to be 1,450 km (900 mi) in length, while the Madeira-Mamoré is estimated near 3,250 km (2,020 mi) or 3380 km in length depending on the measuring party and their methods. The Madeira is the biggest tributary of the Amazon, accounting for about 15% of the water in the basin. A map from Emanuel Bowen in 1747, held by the David Rumsey Map Collection, refers to the Madeira by the pre-colonial, indigenous name Cuyari:

The River of Cuyari, called by the Portuguese Madeira or the Wood River, is formed by two great rivers, which join near its mouth. It was by this River, that the Nation of Topinambes passed into the River Amazon.

The Morona River is a tributary to the Marañón River, and flows parallel to the Pastaza River and immediately to the west of it, and is the last stream of any importance on the northern side of the Amazon before reaching the Pongo de Manseriche.

Pongo de Manseriche

The Pongo de Manseriche is a gorge in northwest Peru. The Marañón River runs through this gorge before it reaches the Amazon Basin.

Ucayali River

The Ucayali River is the main headstream of the Amazon River. It rises about 110 km (68 mi) north of Lake Titicaca, in the Arequipa region of Peru and becomes the Amazon at the confluence of the Marañón close to Nauta city. The city of Pucallpa is located on the banks of the Ucayali.

Department of Loreto Departments of Peru

Loreto is Peru's northernmost department and region. Covering almost one-third of Peru's territory, Loreto is by far the nation's largest department; it is also one of the most sparsely populated regions due to its remote location in the Amazon Rainforest. Its capital is Iquitos.

Department of San Martín Departments of Peru

San Martín is a department and region in northern Peru. Most of the department is located in the upper part of the Peruvian Amazon rainforest. Its capital is Moyobamba and the largest city in the department is Tarapoto.

Urubamba River

The Urubamba River or Vilcamayo River is a river in Peru. Upstream it is called Vilcanota River. Within the La Convención Province the naming changes to Urubamba. A partially navigable headwater of the Amazon River, it rises in the Andes to the southeast of Cuzco. It originates on the slopes of Khunurana in the Puno Region, Melgar Province, near the La Raya pass. It flows north-north-west for 724 kilometers before coalescing with the Tambo River to form the Ucayali River.

Huallaga River

The Huallaga River is a tributary of the Marañón River, part of the Amazon Basin. Old names for this river include Guallaga and Rio de los Motilones. The Huallaga is born on the slopes of the Andes in central Peru and joins the Marañón before the latter reaches the Ucayali River to form the Amazon. Its main affluents are the Monzón, Mayo, Biabo, Abiseo and Tocache rivers. Coca is grown in most of those valleys, which are also exposed to periodic floods.

Biobío River River in Chile

The Biobío River is the second largest river in Chile. It originates from Icalma and Galletué lakes in the Andes and flows 380 km to the Gulf of Arauco on the Pacific Ocean.

Yurimaguas Town in Loreto, Peru

Yurimaguas is a port town in the Loreto Region of the northeastern Peruvian Amazon. Historically associated with the Mainas missions, the culturally diverse town is affectionately known as the "Pearl of the Huallaga". Yurimaguas is located at the confluence of the majestic Huallaga and Paranapura Rivers in the steamy rainforests of northeastern Peru. It is the capital of both Alto Amazonas Province and Yurimaguas District, and had a population estimated at about 62,903 inhabitants (2017).


Rupa-Rupa or High Jungle is one of the eight natural regions of Peru. It is located between 400 and 1,000 m above the sea level to the east of the Andes mountain range in the Amazon basin of Peru. This region has many long, narrow valleys and fluvial mountain trails. The weather is warm, humid, and rainy.

Tena, Ecuador Place in Napo, Ecuador

Tena, the capital of the Napo Province, is a city in the Amazon rainforest. Known as the “cinnamon capital" of Ecuador, and founded by missionary explorers, Tena has emerged as a major commercial center of Ecuador. It is home to a regional hospital and many tourist related businesses, including a small airport and a vital bus terminal.

A pongo is a type of canyon or narrow gorge along rivers in Peru, especially on the Marañón River and its affluents, in the Amazonas Region.

Samuel Fritz SJ was a Czech Jesuit missionary, noted for his exploration of the Amazon River and its basin. He spent most of his life preaching to Indigenous communities in the western Amazon region, including the Omaguas, the Yurimaguas, the Aisuare, the Ibanomas, and the Ticunas. In 1707 he produced the first accurate map of the Amazon River, establishing as its source the Marañón.

Wildlife of Peru

Peru has some of the greatest biodiversity in the world. It belongs to the select group of mega diverse countries because of the presence of the Andes, Amazon rainforest, and the Pacific Ocean. It has the fourth-most tropical forests of any country and the ninth-most forest area.

Source of the Amazon River

The main source of the largest river in the world has been a subject of exploring and speculations for centuries and continues to cause arguments even today. Determining the origin of the Amazon River has evoked broad debates among scholars, explorers, and travelers all over the world. Different definitions of a river's source have been used and continue to be used. Generally, four main criteria can be applied to determine the main source of a river: source flow rate, source length, watershed area of the source, and an altitude of its spring. At present, the Amazon River is not considered to have one unique source but a number of headstream areas. These are headwaters of three different Peruvian rivers that can be found in the high Andes: the Marañón, the Apurímac, and the Mantaro.

Bertrand Flornoy

Bertrand Flornoy was a French explorer and archaeologist.

Santa Ana is an important archaeological site in the highlands of Ecuador, going back as early as 3,500 BC. It is located in the Palanda Canton, just to the north of its regional capital of es:Palanda, in the Zamora-Chinchipe Province of Ecuador.

Marañón dry forests

The Marañón dry forests (NT0223) is an ecoregion in northern Peru. It covers the lower valley of the Marañón River and its tributaries along the eastern edge of the Andes. It has a dry climate due to rain shadow from mountains further east. The habitat has long been modified by farming, ranching and logging and is now threatened by construction of hydroelectric and irrigation dams.


  1. 1 2 3 Church, George Earl (1911). "Amazon"  . In Chisholm, Hugh (ed.). Encyclopædia Britannica . 1 (11th ed.). Cambridge University Press. pp. 786–787.
  2. Sistema Estadístico Nacional (2005). "Teritorio 1.8 Longitud aproximada de los rios mas importantes". Perú: Compendio Estadístico 2005 (PDF). Instituto Nacional de Estadística e Informática (INEI). p. 997.
  3. Samuel Fritz, George Edmundson (1922). Journal of the travels and labours of Father Samuel Fritz in ... Fritz, Samuel, 1654-1724. London, Printed for the Hakluyt Society.
  4. Rittlinger, Herbert (1977). Ganz Allein zum Amazonas. Germany: Büchergilde Gutenberg, Frankfurt am Main. ISBN   3765301965.
  5. Sebastian Snow. My Amazon Adventure. Readers Book Club. ASIN   B003Z01196 . Retrieved 22 February 2013.
  6. "Laszlo Berty: rafting pioneer in Peru". SierraRios. n.d. Retrieved 22 February 2013.
  7. "First Descent of Río Marañon: Fisher, Gaskill, Toll, and Wasson Expedition". SierraRios. Retrieved 22 February 2013.
  8. Tim Biggs. Three Rivers of the Amazon. Amazon. ASIN   B00507FRT2 . Retrieved 10 February 2013.
  9. "First Descent of the Amazon Expedition". Sierra Rios. Retrieved 22 February 2013.
  10. "Peru's Energy Ambitions". The Economist. 12 February 2011. Retrieved 22 February 2013.
  11. "Proyecto Central Hidroeléctrica Veracruz 730 MW" (in Spanish). Sector Electricidad. 23 August 2012. Retrieved 22 February 2013.
  12. AC Energia S.A. (November 2011). "EIA Proyecto CH Chadín" (PDF). Ministerio de Energía y Minas. p. 59. Retrieved 5 May 2016.
  13. "EIS Chadin2 Dam". Estudio de Impacto Ambiental del Proyecto Hydroelectrica Chadin 2, AC Energia S.A. SierraRios. November 2011. p. 30. Retrieved 22 February 2013.
  14.’s Special Reporting Initiatives (26 May 2015). "Peru planning to dam Amazon's main source and displace 1000s". The Guardian. Retrieved 5 May 2016.
  15. "Perú: Se inició obra de Central Hidroeléctrica Chaglla de 406MW - Sector Electricidad - Profesionales en Ingeniería Eléctrica". (in Spanish). 21 August 2012. Retrieved 6 September 2017.
  16. "Save Río Marañon". n.d. Retrieved 22 February 2013.
  17. "Graves impactos de la represa Chadín 2" (PDF). Infographic. Forum Solidaridad Peru. 23 September 2013. Retrieved 5 May 2016.
  18. "Río Marañon". International Rivers. n.d. Retrieved 22 February 2013.
  19. Finer M, Jenkins CN (2012). "Proliferation of Hydroelectric Dams in the Andean Amazon and Implications for Andes-Amazon Connectivity". PLoS ONE. 7 (4): e35126. doi:10.1371/journal.pone.0035126. PMC   3329437 . PMID   22529979.

Coordinates: 7°58′03″S77°17′52″W / 7.967438°S 77.297745°W / -7.967438; -77.297745