The project NANO-CATHEDRAL aims at developing, with a nano-metric scale approach, new materials, technologies and procedures for the conservation of deteriorated stones in monumental buildings and cathedrals and high value contemporary architecture, with a particular emphasis on the preservation of the originality and specificity of materials. The objective is providing “key tools” for restoration and conservation:•On representative lithotypes•On European representative climatic areas•With a time-scale/environmental approach•With technology validated in relevant environment (industrial plant and monuments)•Exploiting results also on modern stone made buildingsA general protocol will be defined for the identification of the petrographic and mineralogical features of the stone materials, the identification of the degradation patterns, the evaluation of the causes and mechanisms of alteration and degradation, including the correlations between the relevant state of decay and the actual microclimatic and air pollution conditions. Moreover, innovative nano-materials will be developed suitable for:•Surface consolidation: in this case water-based formulations based on nano-inorganic or nano-hybrid dispersions such as nano-silica, nano-titania, nano-hydroxyapatite, nano-calcite and nano-magnesia as well as their synergic combinations with organic and inorganic compounds will be considered. •Surface protection: in this case, innovative composites will be developed consisting of polymers and nano-fillers. The use of hydrophobins, nano-assembled hydrofobic proteins extracted from fungi, and photocatalytic nano-particles (for favoring the decomposition of volatile organic molecules carried by polluted atmosphere and to prevent biofilm growth) will be considered.The project will contribute to the development of transnational cultural tourism and to the development of common European shared values and heritage, thus stimulating a greater sense of European identity.