Fig.1 Location of the five surveying sites (1 to 5) and 407 rockfalls, including 284 rockfalls scars and 123 rockfalls deposits, with respect to the YLTP Fault core. Rockfall scars are zoned in 7 main clusters for back analysis of rock mass strength (Fig. 7), A to G, considering similar geometrical characteristics of the rock slopes and rock mass. Our 30-km measurement area covered by UAV at five sites and 10-m DEM for rockfalls identification on the whole slopes traverse along the YLZP river valley. Rockfall iso-density contours obtained through bivariate kernel density estimation by ArcGIS are shown.