Concrete structures may be affected by processes of dissolution of the cement from which they are constructed under the action of water infiltration (ground water, rain, snow), resulting in dripping speleothems (stalactites, stalagmites) and composite dripstone-flowstone genesis (veils, curtains). This study examines three concrete structures, built during the Second World War (bunkers, casemates) in the county of Bistrița-Năsăud, to highlight the mechanisms that govern these processes and their relevance in the scientific and tourism plan.