A five-year conservation project at Cueva de las Monas, one of Chihuahua’s most significant rock art sites, has been completed after specialists worked to stabilise centuries-old paintings threatened by natural deterioration and vandalism.
Mexico’s National Institute of Anthropology and History (INAH) said the project concluded during the first half of 2026, following continuous research and conservation work carried out between 2021 and 2026.
Located on a hillside in the north-eastern Sierra de Majalca, around 59 kilometres north of Chihuahua City, Cueva de las Monas is the largest cave within a wider complex and contains layers of rock paintings spanning more than 2,000 years.
The images, noted for the quality of their brushwork and rich iconography, range from pre-Hispanic traditions to works displaying the influence of Spanish missionaries during the colonial period.
Archaeologist Enrique Chacón Soria, of the INAH Chihuahua Centre, has identified at least three major phases of painting at the site.
The earliest dates to around 300 BC, during the Late Archaic-Transitional period, when the cave is believed to have been used as a camp by Indigenous hunter-gatherer-fisher communities.
A second phase has been associated with the Tarahumara and covers both the pre-contact and colonial periods, particularly the 17th and 18th centuries. Its imagery includes motifs linked to the Tarahumara relationship with peyote alongside symbols associated with Catholicism.
A third phase, dating to around the 19th century, includes representations attributed to Apache groups.
Mexico’s Culture Secretary, Claudia Curiel de Icaza, said the site preserves evidence of communities and traditions from markedly different periods.
“The memory of different peoples and eras converges in the Cave of the Monkeys,” she said. “Its comprehensive care demonstrates that heritage is not only recovered: it is researched, protected, and managed with a vision for the future to ensure its permanence.”
Paintings threatened by weathering and vandalism
Conservators faced significant challenges during the project. Natural weathering and the passage of time had weakened the rock surfaces supporting the paintings, leaving some areas at serious risk of being lost.
Human activity had caused further damage. Sandra Cruz Flores, a restoration specialist with INAH’s National Coordination for the Conservation of Cultural Heritage, said unregulated visitors had left spray-painted, charcoal and pencil graffiti on the cave walls.
Specialists also documented scratches made with sharp objects and evidence that liquids had been thrown onto painted surfaces.
The conservation team carried out detailed restoration work to address these alterations while stabilising particularly fragile sections of the rock.
One of the project’s most important achievements, according to Cruz Flores, was securing areas where paintings faced an immediate risk of loss. Sections damaged by graffiti and other human interference were also treated, improving the visibility and legibility of the original imagery.
The five seasons of fieldwork brought together a multidisciplinary team that recorded and documented the cave, monitored its condition and applied specialist technologies and research methods to better understand both the paintings and the processes responsible for their deterioration.
Long-term protection remains a priority
Although the formal conservation project has now ended, INAH officials say the work represents the beginning of a longer-term strategy for safeguarding Cueva de las Monas.
The research, conservation measures and institutional coordination established during the project are expected to provide the basis for future protection and management of the site.
INAH’s Directorate of Site Operations is now developing an infrastructure proposal intended to improve protection of the cave.
Officials stressed that the objective is not to prepare Cueva de las Monas for mass tourism. The site is not officially open to the public, and any future access would need to be carefully controlled to prevent further damage.
“Rather than making adjustments to accommodate a massive influx of visitors, the goal is to ensure that this heritage remains protected, studied, and known,” Cruz Flores said.
A controlled visitation system could eventually be considered, but specialists warn that the exceptional fragility of the paintings means conservation must remain the overriding priority.
Cruz Flores said protecting the site will require continued specialist intervention as well as responsible behaviour from institutions and the wider public.
Unauthorised tours, physical interventions or other activities that could place the paintings at risk should be avoided, she said, if the remarkable record preserved within Cueva de las Monas is to survive for future generations.
Header Image Credit : Daniel Sánchez
Sources : INAH
