Years of unregulated mining activity have left hundreds of abandoned quarries across Lebanon. Satellite images show that the number of quarries and areas they cover increased, from 784 quarries covering 2897 ha in 1989, to 1278 quarries covering 5267 ha in 2005. This paper presents a comprehensive approach to assess the impact of quarrying activities on scarce Eastern Mediterranean natural resources. The assessment is based on the computation of spatial indicators such as rainfall, slope gradient, vegetation cover, soil erosion risk, and rock infiltration, using GIS to appraise critical impacts on the Lebanese ecosystem. Compared with the 1989 baseline, the area consumed by quarries in 2005 increased more than three times over former arable lands, one third for forest lands and doubled for pasture lands. Quarries additionally destroyed 676, 137, and 737 ha of productive lands, respectively. The comparison of quarry distribution with the land capability map revealed that quarries are found mainly on productive soils, consuming 1314 ha in 1989 and 2192 ha in 2005 of prime lands. A total of 87 per cent of studied quarries represent serious hazards to groundwater quality. In general, a total of 272 quarries have high impact, 657 quarries have moderate impact, and 349 quarries have low impact on natural ecosystems. Analyzed data revealed that around 62 per cent of the quarries are located in a highly unsuitable environment. This paper presents recent findings from the Eastern Mediterranean for territorial suitability assessment of quarries to be considered in the frame of natural resources and coastal ecosystems management. Copyright © 2010 John Wiley & Sons, Ltd.