The hydric properties of three types of building stone used in certain Spanish monuments of outstanding historical-artistic value have been determined. The stones selected were dolomite, limestone and sandstone used in the cathedrals of Leon (northern Spain), Seville (southern Spain) and Salamanca (central Spain) respectively. In the work described in this paper, different rock properties related to water were measured (absorption of water and water vapour, evaporation, capillarity and permeability to water vapour). Swelling characteristics of the sandstone were also determined. The close correlation between the values of the parameters obtained for each property analyzes and the mineralogical-textural features of the rock, notably the porosity and form of the pore system, has been demonstrated. In these stones, it has been observed that water absorption capacity is linked both to the volume of empty communicating spaces (open porosity) and to the presence and percentage of clay minerals. -- CAL