Background Limestone has been an important and popular construction material since the building of the Pyramids. It has been exploited for many uses, particularly in recent years the production of cement and mortar and, when crushed, for use as an aggregate. Limestone quarries are found all over Europe. Quarrying produces dramatic degradation of the landscape and the ecosystems within. It leaves complex restoration problems once commercial exploitation ends. Restorative work has tried to integrate old mining sites into the surrounding area in terms of aesthetics and landscape function - water flow, erosion control, biotic corridors - taking a guide from the surrounding natural ecosystems and landscapes. The topography, soils, and characteristic organisms should all be restored in the quarry areas, but attempts have not always been successful. While the European mining sector is growing rapidly, very few extraction companies have applied for environmental certification. Ecological restoration programmes lack consistency of approach, resulting in unsatisfactory outcomes and low productivity. One reason for low implementation of successful control systems is lack of defined minimum criteria and outcomes. Re-vegetation has been prioritised, but little attention paid to other issues such as diversity of ecosystems and quality of the restored vegetation. Objectives The project EcoQuarry set out to establish sound protocols for quality control in limestone quarry restoration, using best-available scientific and technological knowledge. In particular, the project aimed to demonstrate restoration using native species, bio-solids as organic fertilizers and establishment of successful, cost-effective irrigation maintenance levels and systems. The objective was to use full-scale projects at a number of diverse quarry sites representative of various Mediterranean substrate and climate conditions. Of these, ten were around the Catalonia and Valencia regions of Spain and one in Alentejo, Portugal. Input came from the beneficiary university plus six research centre partners - from Spain and Portugal - as well as the environment department of Catalonia and the region’s two main mining-sector trade associations. Resulting procedures were to be published in a manual and disseminated to companies working in the concrete and aggregates sectors, and to authorities responsible for monitoring quarry restoration. Results The project succeeded in developing the quality control schemes required during the various phases of limestone quarry restoration to integrate the areas back into the landscape and recover functional ecosystems. It established principles of restoration ecology for assessing and designing the minimum requirements needed to trigger natural succession in the middle term. It promoted and demonstrated successful use of local materials for substrates; re-introduction of native species; and established minimum levels of inputs - especially watering. Part of the project period included a drought and this produced valuable water-management data, including in use of sprinkler systems. Comparative results for sowing systems and control of vegetation were achieved and analysed. Studies of soil erosion using rain simulation highlighted improvements needed in protection and drainage methods. Among the findings were: Some species of shrubs can be sown directly, reducing the cost of conventional restoration. Development of sown plants depends very much on the origin or quality of substrate. In the first phases after sowing, amended inert mineral waste released better results than substrates obtained with external soil material - usually from old fields - which carry a lot of weed. For stony substrates, frequent irrigation is more important than irrigation quantity in plant survival and growth. In substrates with poor structure, application of organic amendments reduces erosion rate. The effect of amendment is greater than the effect of plant cover in controlling soil erosion.The resulting booklet “Guidelines for limestone quarry restoration in Mediterranean climate” now provides assessment and guidance on best practice and techniques to achieve sustainable quarry restoration and quality control. It will be used by enterprises and technical staff in the cement and aggregate sectors and provides a scientific and technical basis for regulation from regional to European levels. Direct participation of quarry associations and environmental administrators has already increased interest and promoted swift dissemination of the project results to the mining sector. Work will continue because the beneficiary has signed an agreement with the trade guilds to build on this LIFE project. The criteria developed are directly applicable to any EU country, and interest has come from a wider area. Students from the US, Australia and Argentina were among those to visit the sites.