The snow wells of Sierra Espuña (28 inventoried examples) are a distinctive group of proto-industrial structures: circular cisterns excavated into rock and roofed by stone or brick domes, once functioning as local ice factories. From the 16th century until the early 20th century, winter snow was gathered on surrounding “rasos” (esplanade), compacted and stored in these wells to produce ice for summer use and for transport—sometimes to towns up to 100 km away. This activity generated a whole cultural landscape of tracks, shelters, orchards and logistical nodes. With the advent of mechanical refrigeration, the wells fell into disuse; domes collapsed, ancillary buildings deteriorated and the complex risked disappearing. Today they stand both as material heritage and as visible witnesses of climatic change: contemporary snowfalls in the mountain are scarce, rendering their original function practically impossible.
Why intervene: aims, context and institutional backing
In 2019 the Regional Government of Murcia commissioned a Master Plan to inventory, study and define a strategy for the entire ensemble. The Master Plan was prepared by the architecture studio Ecoproyecta and combined archival research with extensive field survey. The General Directorate of Cultural Heritage initiated the project, which was later implemented by the General Directorate of Natural Environment. The Plan established a roadmap: document the 28 wells and associated features (houses, a chapel, orchard, spring, paths and “rasos”), delimit a protection area, and prioritize conservation, landscape and interpretation actions. As an initial technical phase, Wells 11 and 13 were selected for urgent restoration because they combined high vulnerability with sufficient surviving fabric and archival evidence to permit faithful recovery.
The project pursued complementary objectives: stabilize representative examples and reinstate their original geometry; recover and reuse traditional materials and techniques; integrate conservation with the protected mountain landscape; and enable safe, intelligible public access that communicates the wells’ technological and social history without compromising ecological values. The Master Plan created a phased program that has guided the work since 2019 and has been instrumental in securing further funding. Following international recognition — the Europa Nostra Award 2024 was granted for the restoration of Wells 11 and 13 undertaken by Ecoproyecta and specialist partners — the Association of Sierra Espuña Municipalities obtained a major grant from Spain’s Ministry of Tourism to consolidate ten additional wells, restore four ancillary buildings and reconstruct two more wells by 2026.
Two restored snow wells
Methodology and technical approach
The restoration team combined archival and field research, archaeological recording, structural analysis and traditional craft. Early field work removed accumulated sediments—often two metres deep—to reveal original bases and the footings of domes. Archaeological recording documented construction traces, original bonding patterns and remaining brick courses that established the dome geometries. Well 11, for example, is the largest in the ensemble (approximately 12 m diameter and 12 m depth), with a mixed stone-and-brick dome typology; Well 13 retained part of a false dome constructed by approximation of courses and a conical profile. Tackling these two different systems provided a technical demonstration of two historic building technologies.
Conservation followed principles of authenticity, minimal intervention and material compatibility. Fallen voussoirs and rubble were carefully recovered, cleaned and catalogued on site; reused stone comprises the bulk of the consolidation work, significantly reducing transport and embodied carbon. Where original bricks were too degraded, new handmade bricks were manufactured locally (Valentín brickworks) replicating original formats after precise measurement of extant units. Laboratory analysis of historic mortars informed the design of lime-based binder mixes used for repointing and parging; pre-construction mortar trials validated colour, texture and physical performance. During dome reconstructions, timber formwork (“cimbra”) and an inner/outer scaffolding system ensured safe execution and enabled sequential laying of masonry courses. Structural load tests were carried out on representative sections prior to final closure of the domes.
All interventions were reversible where feasible, and new elements intended for visitors were designed to be visually legible and lightweight: an observation deck and internal stair at Well 11 and a timber walkway across the void at Well 13, both crafted in wood to contrast with historic masonry. Working in the landscape and capacity building
Sierra Espuña is a protected natural area; therefore, environmental safeguards were integral from the outset. The study and siting of access, material stockpiles and working areas were determined in consultation with ecologists. Landscape measures included recovery of “rasos”, removal of non-native reforestations that had altered original topography, and replanting with native species to restore the historic setting. These measures reduce the long-term visual impact of works and reinforce habitat values.
The project also addressed skills and craft shortages by prioritising work with local stonemasons and brickmakers, and by organising on-site training modules that transmitted traditional masonry, lime work and dome-building techniques. This capacity-building component is considered key to the long-term maintenance of the ensemble and as a model for rural heritage programmes elsewhere.
Inside the number 11 snow well
Impact, governance and lessons
The conservation of Wells 11 and 13 has delivered immediate outcomes—stabilised domes, recovered interiors and accessible interpretation—while also functioning as a proof of method for the larger programme now enabled by Ministry funding. The intervention demonstrates the benefits of a phased Master Plan, robust archival and technical study, and sustained inter-institutional cooperation: heritage authorities, regional environment directorates, municipal bodies, specialist contractors and local craft producers have all contributed.
Challenges remain typical of mountain heritage work: difficult access for equipment, logistic complexity, scarcity of specialist craftspeople and the necessity of balancing visitation with conservation. The project’s strengths lie in its research-based methodology, use of in-situ materials, integration of environmental restoration and the combination of traditional techniques with modern safety standards.
Conclusion
The Sierra Espuña programme offers a concise model for integrated conservation: a landscape-based Master Plan that sequences emergency stabilisation, technical recovery and wider landscape rehabilitation; an emphasis on material authenticity and low-impact practices; and a combined cultural-ecological perspective that strengthens both heritage and biodiversity. Having secured recognition at the European level through the Europa Nostra Award for the work led by Ecoproyecta, and further funding for consolidation and restoration through to 2026, the project now aims to extend its methodology across the ensemble and to sustain the skills and institutional collaborations necessary to preserve this singular mountain heritage for future generations.