This thesis addresses the issue of rockfall instability, focusing on identifying and analyzing areas prone to rockfall events. Specifically, it examines a slope in Varallo (VC, North-West Italy) that has experienced repeated rockfall phenomena over the years, posing risks to the buildings and the adjacent road at its base. Given the need to evaluate large areas, preliminary methods are essential to pinpoint zones requiring detailed analysis. To meet this need, the QPROTO plugin, integrated within QGIS, was used to quantitatively assess time-independent rockfall hazards across three-dimensional terrains using the Cone Method. This approach requires specific input angles, such as the energy angle (φp) and the lateral angle (α), which capture the complex dynamics of rock block movement along slopes.