‘They weren’t burned by accident’: burned stone, child’s bones, and lost jewelry could reveal prehistoric mining camp high in the Pyrenees
Archaeologists uncover possible evidence of ancient copper smelting spanning more than 2,000 years in a mountain cave more than 2,000 meters above sea level
image:
Malachite fragments, a mineral rich in copper, recovered during the excavation works at Cova 338. Authorship: Maria D. Guillén / IPHES-CERCA.
view moreCredit: Maria D. Guillén / IPHES-CERCA.
High in the eastern Pyrenees, archaeologists are revealing the secrets of a prehistoric cave full of hearths containing fragments of green rock that could represent early copper mining. People visited this site for well-planned, well-supplied trips spanning two thousand years, overturning previous assumptions that prehistoric peoples didn’t spend long periods at high altitude. The discovery of a child’s finger bone and baby tooth suggest that, after more excavations, we may find that it was also a burial site.
“For a long time, high-mountain environments were seen as marginal, places prehistoric communities passed through occasionally,” said Prof Carlos Tornero of the Catalan Institute of Human Paleoecology and Social Evolution, lead author of the article in Frontiers in Environmental Archaeology. “But we found a really rich archaeological sequence, including multiple combustion structures and a very large number of green mineral fragments. We can’t say exactly how long people stayed each time, but the repeated use of the space and the density of remains suggest occupations that were short to medium in duration, but happening again and again over long periods of time.”
Burning questions
Cave 338 is found at 2,235m above sea level in the Freser Valley. The scientists excavated an area of 6m2 at its entrance, identifying four layers of occupation. The first, most recent layer was thin, showing the cave was not frequently used at that time, and contained some artefacts from historical periods. The fourth, oldest layer contains only charcoal fragments, dated at 6,000 years old.
The researchers hit the jackpot in the second and third layers of the excavation: a total of 23 hearths, containing many crushed, burned green mineral fragments. In-depth material analysis to confirm its identity is underway, but the fragments resemble malachite, which can be treated like this to produce copper. Cave 338 looks like an unexpectedly early high-altitude mining camp.
“Many of these fragments are thermally altered, while other materials in the cave are not, which clearly suggests that fire played an important role in their processing and that there was a deliberate intention behind it,” said Dr Julia Montes-Landa of the University of Granada, co-author. “In other words, they weren’t burned by accident.”
The hearths cut across each other, indicating that the visitors reused this space frequently, but are still distinct, which suggests that those visits were separated by plenty of time. Radiocarbon dating puts the hearth found in the second layer at about 3,000 years old, while the hearths in the third layer are around 5,500 to 4,000 years old.
Secrets of the mountains
The team also found human remains in the third layer — a finger bone and a baby tooth belonging to at least one child, about 11 years old — which could mean there are burials deeper within the cave. However, there isn’t enough evidence to suggest a cause of death or determine if the two bones belonged to the same child. Jewelry found in the second layer offered more information.
“We recovered two pendants: one made from a shell and another from a brown bear tooth,” said Tornero. “They come from prehistoric contexts, most likely around the second millennium BC. The shell pendant is interesting because it has parallels in other sites in Catalonia, which suggests shared traditions or connections between different communities. The bear tooth pendant is much less common. That might point to something more specific or symbolic, possibly linked to the local environment.”
Cave 338 wasn’t a full-time home, but the people who came here found their trips valuable enough to keep returning for millennia. The researchers still have a lot of questions about those trips which they hope to answer with future research. For example, further excavation will help us understand more about how and when humans used the cave. They also want to confirm the exact identity of the green mineral and find out where it came from.
“The identification of the green mineral as malachite is still preliminary,” explained Tornero. “The research ongoing by the University of Granada and the Autonomous University of Barcelona will provide final answers shortly. Also, the excavation hasn’t yet reached the full depth of the site, so the sequence is not completely documented. This summer we will continue the archaeological work.”
Archaeological excavation works at Cova 338 from the inside. Authorship: IPHES-CERCA.
Detail of the pendant made of Glycymeris sp. recovered during the excavation works at Cova 338. Authorship: IPHES-CERCA.
Pendant made from a bear incisor recovered during the excavation works at Cova 338. Authorship: IPHES-CERCA.
Journal
Frontiers in Environmental Archaeology
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Beyond 2000 meters, first evidence of intense prehistoric occupation in the Pyrenees
Article Publication Date
5-May-2026
Above 2,000 meters: Cova 338 redefines Pyrenean prehistory
Universitat Autonoma de Barcelona
image:
Archaeological excavations in the interior of Cova 338. Authorship: IPHES-CERCA.
view moreCredit: IPHES-CERCA.
Above 2,000 meters: Cova 338 redefines Pyrenean prehistory
- The site, located in the Núria Valley, documents recurrent human occupations spanning more than 5,000 years and provides some of the earliest evidence of copper-rich mineral exploitation in Western Europe
- The study, led by the Universitat Autònoma de Barcelona and IPHES-CERCA and published in Frontiers in Environmental Archaeology, challenges the traditional view of high mountain areas as marginal
An international research team led by the Universitat Autònoma de Barcelona (UAB) and the Institut Català de Paleoecologia Humana i Evolució Social (IPHES-CERCA) has documented the highest-altitude prehistoric cave with evidence of intense human occupation known to date in the Pyrenees. The site, known as Cova 338, is located at 2,235 meters above sea level in the Núria Valley (Queralbs, Ripollès - Girona) and currently represents the most significant high-mountain prehistoric site documented in the range.
The results show that the cave was repeatedly occupied between the 5th millennium BCE and the end of the 1st millennium BCE, providing new evidence on the exploitation of high-mountain resources in prehistoric times and challenging the traditional idea that these areas were used only sporadically or marginally. Dating indicates that these occupations occurred in several distinct phases, separated by periods of abandonment, suggesting a planned and recurrent use of this space.
This is the main conclusion of the article published in Frontiers in Environmental Archaeology, led by Carlos Tornero, professor in the Department of Prehistory at the UAB and researcher at IPHES-CERCA, with the participation of researchers from IPHES-CERCA, the Universitat Rovira i Virgili, the University of Granada, the Pompeu Fabra University, and the University of the Balearic Islands, among other institutions.
Intense and organized occupation in a high-mountain environment
For decades, archaeological research has interpreted areas above 2,000 meters in altitude as marginal territories, occupied only occasionally. Cova 338 breaks with this model.
Extensive excavations carried out between 2021 and 2023 have revealed “an exceptional archaeological sequence, including numerous combustion structures, faunal remains, ceramic fragments, and a remarkable assemblage of green minerals, likely malachite, a copper-rich mineral”, explains Carlos Tornero. “For the first time in the Pyrenees, high-mountain prehistoric occupations of significant intensity have been documented, characterized by repeated activities and the direct exploitation of mineral resources within the cave.”
Among the recovered materials are also two pendants: one made from a marine shell (Glycimeris) and another from a brown bear tooth, evidencing personal ornamentation practices. The former has parallels in other Catalan sites, while the latter is much rarer and possibly linked to a specific symbolic meaning.
“Cova 338 forces us to rethink the role of high mountain environments in Pyrenean prehistoric societies”, highlights Carlos Tornero. “For a long time, these spaces were assumed to be marginal. What we document here is recurrent occupation, with complex activities and a clear exploitation of mineral resources.”
The evidence suggests that mineral fragments were brought into the cave and subsequently fragmented or processed inside, indicating systematic exploitation of copper-rich minerals in a high-mountain environment throughout the Late Neolithic and the Bronze Age. These data place Cova 338 among the earliest known examples of this type of activity in Western Europe.
Spatial analysis of the site shows a clear internal organization of activities, with differentiated structures and areas. Researchers interpret the cave as a logistical site integrated within well-structured seasonal mobility systems, where human groups returned recurrently to carry out specific tasks.
“The mountain was not a barrier, but an active place within the economic and territorial organization of prehistoric communities”, notes Eudald Carbonell, researcher at IPHES-CERCA and co-author of the study.
A research project under extreme conditions
The research is part of the ARRELS project, a program promoted by the Ministry for Culture of the Government of Catalonia and led by the UAB and IPHES-CERCA, focused on studying the prehistoric roots of human mobility and occupation in the Upper Ripollès region.
Excavations at Cova 338 have posed a major logistical challenge, as access to the cave is only possible on foot from the Núria Valley, with no motorized support allowed. This has required all materials and sediments generated during the digs to be transported manually.
“Conducting an archaeological excavation to current scientific standards under these conditions is extraordinarily demanding”, explains Tornero. The work incorporated high-resolution methodologies, including 3D recording of all materials, systematic sediment sampling, and techniques such as washing and flotation, which allow even the smallest remains to be recovered and provide highly detailed information on the activities carried out in the cave.
Given its scientific importance and excellent state of preservation, the site has been protected and access restricted to ensure the conservation of the deposits and facilitate future research.
The work has also been made possible thanks to the logistical and institutional support of the Queralbs Town Council and the Ter and Freser Headwaters Natural Park, which have facilitated fieldwork in this high-mountain environment.
A key reference for European prehistory
Researchers consider Cova 338 to be a key reference for understanding human occupation of the Pyrenean high mountains and the exploitation of their resources during recent prehistory.
“This site demonstrates that the Pyrenees were not a marginal territory for prehistoric communities, but a space fully integrated into their mobility strategies and territorial exploitation”, concludes Carlos Tornero.
The results open new lines of research into the role of alpine environments in prehistoric societies and the earliest forms of mineral resource exploitation in high-mountain contexts.
Funding source:This research is funded through the project led by Carlos Tornero and Eudald Carbonell Arrels prehistòriques de la transhumància a l’Alt Ripollès: projecte arqueològic 2022–2025 (code CLT009/22/00060; AGAUR-DGPC, Departament de Cultura, Generalitat de Catalunya) and has had the logistic and institutional support of the Queralbs Town Council and the Ter and Freser Headwaters Natural Park, which have facilitated the development of the excavations in this high mountain environment.
Journal
Frontiers in Environmental Archaeology
Article Title
Beyond 2,000 meters, first evidence of intense prehistoric occupation in the Pyrenees
