Field monitoring and laboratory results are presented for an unsaturated volcanic pyroclastic. The pyroclastic is constantly affected by intense erosion, collapse and liquefaction. The pyroclastic can also move as an undisturbed block of material (a combination between fall and of topple), sand/silt/debris flowslide and debris avalanche during the rainy season or earthquakes. This type of material and the uncontrolled urbanization aggravate the environmental, social and economic damages of the region. Most of the slopes are almost vertical and temporally stable, but will collapse when wetted or during seismic events. Wetting of the soil is likely to occur following construction development, because evaporation is reduced by covering the ground surface with a structure. Is possible to conclude that not only climatic factors as rain quantity, temperature and evaporation are important into landslide susceptibility but also information of suction-moisture content, seepage, topography, weathering, ground deformation, vibrations, cracks, vegetation/roots and the presence of crust covering the surface are necessary to research in each site.