The paper presents the results of an extensive study, performed on strong earthquakes (moment magnitude larger than 6.0) recorded in Romania in the last 30 years. The study involved mapping of peak ground motion ordinates, as well as of linear and nonlinear spectral ordinates, for seismic events recorded in 1986, 1990 and 2004. In the first part of the study, shake maps were generated for peak ground acceleration, velocity and displacement, effective