The here presented study analyses the combined role of geological and morphological features on the evolution of an ongoing gravitational slope deformation, located in the western portion of the Mt. Genzana Ridge (central Italy). The latter partly evolved in a huge rock-avalanche responsible for damming the Tasso River valley and originating the Scanno Lake. A morpho-structural multi-stage model of the Quaternary evolution of the slope was reconstructed through geomorphological analyses and a time-dependent morphometric approach. Based on the morpho-evolutionary model we performed a stress-strain numerical modeling to back-analyze the processes that led to the onset of the rockslope deformation. The numerical analysis took into account: i) age constraints derived from morpho-evolutionary model; ii) engineering-geological model based on equivalent continuum approach and a statistical distribution of geomechanical parameter together with targeted laboratory tests; iii) regional stress-field regime variation connected with tectonic activity; iiii) viscous time-dependent behavior. In this paper the results of the multi-modeling approach are presented presents and discussed.