The Ucayali River ( es, Río Ucayali, ) is the main headstream of the

Amazon River The Amazon River (, ; es, Río Amazonas, pt, Rio Amazonas) in South America is the largest river by discharge volume of water in the world, and the disputed longest river system in the world in comparison to the Nile. The headwaters of t ...

. It rises about north of

Lake Titicaca Lake Titicaca (; es, Lago Titicaca ; qu, Titiqaqa Qucha) is a large freshwater lake in the Andes mountains on the border of Bolivia and Peru. It is often called the highest navigable lake in the world. By volume of water and by surface area, i ...

, in the Arequipa region of

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

and becomes the Amazon at the confluence of the Marañón close to

Nauta Nauta is a town in the northeastern part of Loreto Province in the Peruvian Amazon, roughly south of Iquitos, the provincial capital. Nauta is located on the north bank of the Marañón River, a major tributary of the Upper Amazon, a few miles ...

city. The city of

Pucallpa Pucallpa (, qu, puka allpa, lit=red dirt; Shipibo language, Shipibo: ''May Ushin'') is a city in eastern Peru located on the banks of the Ucayali River, a major tributary of the Amazon River. It is the capital of the Ucayali region, the Corone ...

is located on the banks of the Ucayali.

Description

The Ucayali, together with the

Apurímac River The Apurímac River ( que, Apurimaq mayu; es, Río Apurímac, ; from Quechua ''apu'' 'divinity' and ''rimaq'' 'oracle, talker') rises from glacial meltwater of the ridge of the Mismi, a mountain in the Arequipa Province in the south-western ...

, the

Ene River The Ene River ( es, Río Ene; que, Iniy mayu) is a Peruvian river on the eastern slopes of the South American Andes. Geography Headwaters The Ene is formed at at the confluence of the Mantaro River and the Apurímac River, circa 400 m abov ...

and the Tambo River, is today considered the main headwater of the ''Amazon River'', totaling a length of from the source of the ''Apurímac'' at

Nevado Mismi Mismi is a mountain peak of volcanic origin in the Chila mountain range in the Andes of Peru. A glacial stream on the Mismi was firmly identified as the most distant source of the Amazon River in 1996; this finding was confirmed in 2001 and ag ...

to the confluence of the Ucayali and

Marañón River , name_etymology = , image = Maranon.jpg , image_size = 270 , image_caption = Valley of the Marañón between Chachapoyas ( Leimebamba) and Celendín , map = Maranonrivermap.png , map_size ...

s: *Apurímac River (total length): *Ene River (total length): *Tambo River (total length): * Ucayali River (confluence with Tambo River to confluence with the Marañón):

Exploration

The Ucayali was first called ''San Miguel'', then ''Ucayali'', ''Ucayare'', ''Poro'', ''Apu-Poro'', ''Cocama'' and ''Rio de Cuzco''.

has organised many costly and ably-conducted expeditions to explore it. One of them (1867) claimed to have reached within of

Lima Lima ( ; ), originally founded as Ciudad de Los Reyes (City of The Kings) is the capital and the largest city of Peru. It is located in the valleys of the Chillón River, Chillón, Rímac River, Rímac and Lurín Rivers, in the desert zone of t ...

, and the little steamer "Napo" found its way up the violent currents for above the junction with the

Pachitea River The Pachitea River is a river in Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = National seal , nat ...

, and as far as the Tambo River, from the confluence of the Ucayali with the Amazon. The "Napo" then succeeded in ascending the

Urubamba River The Urubamba River or Vilcamayo River (possibly from Quechua ''Willkamayu'', for "sacred river") is a river in Peru. Upstream it is called Vilcanota River (possibly from Aymara ''Willkanuta'', for "house of the sun"). Within the La Convención ...

upstream from its junction with the Tambo, to a point north of

Cuzco Cusco, often spelled Cuzco (; qu, Qusqu ()), is a city in Southeastern Peru near the Urubamba Valley of the Andes mountain range. It is the capital of the Cusco Region and of the Cusco Province. The city is the seventh most populous in Peru; ...

Navigation

Its width varies from , due to the large number of islands. The current runs from , and a channel from wide can always be found with a minimum depth of . There are five difficult passes, due to the accumulation of trees and rafts of timber. Sometimes large rocks which have fallen from the mountains and spread over the river-bed cause whirlpools.

National Reserve

Ucayali is home to the

Amazon river dolphin The Amazon river dolphin (''Inia geoffrensis''), also known as the boto, bufeo or pink river dolphin, is a species of toothed whale classified in the family Iniidae. Three subspecies are currently recognized: ''I. g. geoffrensis'' (Amazon river ...

giant otter The giant otter or giant river otter (''Pteronura brasiliensis'') is a South American carnivorous mammal. It is the longest member of the weasel family, Mustelidae, a globally successful group of predators, reaching up to . Atypical of muste ...

, and the Amazonian manatee, which are abundant in

Pacaya-Samiria National Reserve Pacaya–Samiria National Reserve, is a protected area located in the region of Loreto, Peru and spans an area of . It protects an area of low hills and seasonally flooded forest in the Amazon rainforest. Pacaya-Samiria National Reserve and the ...

, close to Nauta. The southeastern border of the reserve is formed by the lower Ucayali River. The river gives its name to the

Ucayali Region Ucayali () is an inland department and region of Peru. Located in the Amazon rainforest, its name is derived from the Ucayali River. Its capital is the city of Pucallpa. It is the second largest department in Peru, after Loreto. Geography ...

and the

Ucayali Province The Ucayali Province is one of the eight provinces in the Loreto Region of Peru. It was created on October 13, 1900, by president Eduardo López de Romaña. Its territory is mostly flat except for the Ganso Azul mountain range in its eastern part. ...

of the Loreto Region.

References

External links

{{Authority control Rivers of Peru Tributaries of the Amazon River Rivers Rivers of Ucayali Region Upper Amazon