This is a computer program for the three-dimensional simulation of rock-falls.  We developed a 3-dimensional simulation program that starting from thematic information available in digital format and using GIS technology, generates simple maps useful to assess rock-fall hazard. The program requires as input a DTM, the location of rock-fall detachment areas, the dynamic friction coefficient used to simulate the loss of velocity during rolling, and the coefficients for normal and tangential energy restitution at the impact points.