Expedition to Rio Guaporé Jungle: Great Mystery of Lost City of Labirinto
The Guaporé River (also known as the Iténez River, 1,749 km long) originates in Brazil's Mato Grosso state and flows northwest, eventually merging into the Mamoré River. Its course forms the border between Bolivia and Brazil, specifically between the Bolivian departments of Santa Cruz and Beni and the Brazilian states of Mato Grosso and Rondônia.
Since the time of the Incas, the Guaporé River has represented a boundary, beyond which lay mythical and little-known lands, such as the legendary Paititi. Below is an excerpt from the Spanish writer Sarmiento de Gamboa in his Historia de los Incas (1570):
And along the road now called Camata, [Tupac Inca Yupanqui] sent another great captain named Apo Curimache, who went to where the Sun rises and walked to the river now newly known as "Paititi," where the Moxos of Inca Topa live.
The legendary kingdom of Paititi was identified near a river of the same name and was associated with the lands of the Moxos people. According to Sarmiento de Gamboa, the Incas maintained friendly relations with the kingdom of the Moxos and the inhabitants of Paititi but built two fortresses to mark the limits of the Inca Empire's influence. One of these fortresses has been identified near Riberalta, at the confluence of the Beni and Madre de Dios rivers, but the location of the second fortress remains unknown.
According to Lizarazu’s chronicles (1635), the Incas not only built these fortresses but also established control over the kingdom of Paititi. Below are two excerpts from the ancient chronicle:
The Inca of Cusco sent his nephew Manco Inca, the second to bear this name, to conquer the Chuncho people, the Carib Indians living in the jungle east of Cusco, Chuquiago, and Cochabamba. Manco entered the jungle with 8,000 armed Indians, taking his son with him. And considering the difficulty of the terrain, [Manco] settled on the opposite side of the mountain of Paititi. The Guaraní Indians, who later learned of this mighty lord, said that in this mountain there is a great quantity of silver, which they extract, refine, and transform into pure silver. Just as he ruled the kingdom of Cusco, he now rules the grand kingdom of Paititi, called Moxos.
Is it possible that this Manco (not to be confused with Manco Inca) actually ruled Paititi?
Additionally, other ancient documents narrate the flight of Guaynaapoc (Manco's son) to Paititi with the purpose of hiding the sacred symbols of the Tahuantinsuyo in a secret, safe, and distant location from Cusco. Below is an excerpt from Felipe de Alcaya’s chronicle, published in Lizarazu’s Información (1635):
When the "little king" [Guaynaapoc] finally arrived in the city of Cusco, he found the entire land conquered by Gonzalo Pizarro, his uncle [Huáscar] murdered by the King of Quito [Atahualpa], and the other Inca withdrawn to Vilcabamba [Manco Inca].And at that particular moment, he gathered all the Indians loyal to him and invited them to follow him to the new land discovered by his father [Manco], called Mococalpa (now called Moxos)… About twenty thousand Indians followed Guaynaapoc, bringing with them many livestock and silver artisans. Along the way, more indigenous people from the plains joined the multitude, which eventually reached the Rio Manatti (1).
And finally, they arrived at Paititi, where he was joyfully received by his father and other soldiers, his happiness doubled by being in an impregnable kingdom far from Cusco, which was already in the hands of the invaders.
(1) Guaporé River
This legendary place, Paititi, also considered a mystical and ritual land where ancient traditions are preserved, has been sought for over 500 years in countless expeditions, but no one has ever found it.
It has been searched for in Peru, Bolivia, and even Brazil, but no definitive evidence of its existence has ever been discovered.
During my recent trip to Bolivia and Brazil, I was able to complete several expeditions aimed at shedding light on this ancient mystery.
In Bolivia, together with researcher and pilot Jorge Velarde, I conducted an aerial exploration of the Noel Kempff Mercado National Park to identify key clues about these ancient cultures from above. The expedition was a success, as we documented dozens of human-modified lakes oriented along a northeast-southwest axis, along with numerous earthworks and artificial mounds.
In Brazil, I collaborated with researchers from Rondônia state to carry out several expeditions in the basins of both the Rio Machado and the Rio Guaporé.
Our expedition into the Guaporé jungle was aimed at uncovering possible remains of Inca or pre-Inca cultures that could be linked to the legendary journey of Manco and the return of his son Guaynaapoc to the land of Paititi.
The target area was a stretch of jungle near the Forte Príncipe da Beira, an imposing fortress built by the Portuguese in 1776 to mark and control the territory west of the Guaporé River, which had belonged to Portugal since 1750 (per the Treaty of Madrid).
On the western side of the Guaporé River, the Spanish had already constructed the Santa Rosa mission in 1743, but it was short-lived as the Portuguese had taken control of the entire area.
The members of our expedition included:
- Indigenous affairs expert Evandro Santiago,
- History and Philosophy professor Zairo Pinheiro,
- Researcher Joaquim Cunha da Silva,
- Myself, and
- Our local guide, Elvis Pessoa.
We ventured into the jungle to a location about four kilometers from the grand Forte Príncipe da Beira. After walking through the forest for about half an hour, we stumbled upon some unusual ruins—ancient walls approximately two meters high.
Continuing south, we found another wall, this time standing about four meters high and stretching approximately 15 meters in length. The construction was rustic, built with medium-sized stones that were loosely fitted together, not forming a perfect alignment.
After about 20 meters, we encountered another large wall on the opposite side of the first one (toward the east), creating the appearance of a canyon-like structure. The vegetation within the canyon was so thick and dense that it was difficult to distinguish many details without getting close to the walls. Then, once again on the right-hand side, I noticed that the wall formed a channel heading west, narrower but completely overgrown with dense vegetation.
We continued moving forward with difficulty until we came upon a strange stone structure, square in shape, approximately 5 meters on each side, with an entrance through a portal facing north.
The sides of the structure were composed of dilapidated walls about 50 cm high, while the portal was relatively well-preserved. It featured a lintel about 1 meter wide that supported the rustic stones above it. The façade of the portal stood approximately 2.3 meters tall.
Our guide, Elvis, informed us that the entire archaeological site is referred to by the few local natives as "Cidade Labirinto" ("Labyrinth City" in Portuguese).
Throughout the day, we continued exploring the area and realized that the Rio Guaporé is quite far from the Labyrinth City—more than a kilometer away. We also examined the elevated mounds enclosed by the tall, rustic walls, finding irregular residential spaces about two meters wide, demarcated by imperfectly fitted stones.
The following morning, we explored a zone to the east of the portal, about 700 meters away, where we also found several residential spaces or remnants of old foundations. However, the tall walls characteristic of Labyrinth City were absent.
We then returned to the Labyrinth, focusing not only on the intriguing portal—where sediment layers in the soil were about 50 centimeters thick—but also on the walls and the ancient foundational bases located atop them.
Once our exploration was complete, we spent several days in the riverside town of Costa Marques, during which we debated the actual origin of Labyrinth City.
The fact that the Portuguese Forte Príncipe da Beira is only 4 kilometers away suggests the possibility that Labyrinth City served as a quarry. Stones may have been extracted and processed there by the Portuguese in 1776 before being transported to the fort using boats along the current of the Rio Guaporé.
According to some researchers from Rolim de Moura, the portal might have been constructed to store Portuguese munitions in a secure location far from the fort. However, these researchers fail to explain why walls up to 5 meters high were built using rustic techniques, or why there are foundational remains of residential spaces atop these elevated areas.
Furthermore, they do not clarify why the Portuguese, operating with a Western logic, would construct a north-facing portal in the middle of the jungle, precisely in a location previously inhabited by indigenous peoples.
In my opinion, Labyrinth City is highly interesting from both a historical and archaeological perspective. Although no definitive conclusions can be drawn due to the lack of proper excavations thus far, several hypotheses can be proposed.
The tall walls (at least four, though there may be more) were likely not built by 18th-century Europeans, as they are rustic and imperfect. Their apparent purpose seems to have been to demarcate elevated zones—mounds—on top of which there are remnants of residential foundations. These foundations, based on their shape and structure, do not appear to have been constructed or used by Spaniards or Portuguese.
It is also unlikely that the high walls were built by indigenous peoples of the Amazon lowlands, as they historically lacked the need or skill to construct stone structures.
Labyrinth City could therefore have been built by unknown Andean indigenous peoples or perhaps descendants of the Inca royal family who hid on the western bank of the Guaporé River, as suggested by Felipe de Alcaya's chronicles.
As for the portal, opinions vary. Even if Labyrinth City was used as a quarry where the Portuguese extracted stones, why would they construct a single portal facing north? It would not have been for residential purposes—if that were the case, more portals would have been built. Could it have been to hide munitions? While possible, this remains unproven.
Without a serious archaeological excavation campaign, it is currently impossible to provide a clear and definitive answer to the mystery of Labyrinth City.
My final opinion is that the entire area was once inhabited by indigenous peoples of the Amazon lowlands. There is a real possibility that Labyrinth City was modified by Inca descendants and used as a ceremonial center for approximately 200 years (from 1540 to 1740 CE). With the arrival of Europeans in the area, it may have been abandoned and later repurposed by the Portuguese as a quarry for stones used in constructing Forte Príncipe da Beira.
Many Inca-origin axes and a variety of ceramics have been found in the area. Some ceramic fragments are refined and expertly designed, while others are rustic and may have been used merely as containers.
If the Inca origin of the tall walls in Labyrinth City were proven, it could be speculated that it served as a ceremonial center where Huascar's descendants revived ancient traditions. It might also have been used to regroup with the goal of founding a more substantial city—the legendary Paititi—further inland and relatively distant from the Guaporé River.
Could it be located within the Pacaás Novos National Park, near the Tracoá (Jaru Peak), the highest mountain in Rondônia?
YURI LEVERATTO
