The source characteristics of the 1930 Irpinia earthquake (Imax=X) are inferred through the comparison among the macroseismic field and the ground acceleration fields associated with some different source models proposed in literature for the earthquake. Moreover, we converted the simulated PGAs for some towns in intensities. In order to minimize the misfit among simulated and real intensity data, we moved the fault position with respect to the bibliographic location about 10 km toward SW.