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Inadequate seismic design codes can be dangerous, particularly when they underestimate the true hazard. In this study we use data from a sequence of moderate‐sized earthquakes in northeast Italy to validate and test a regional wave propagation model which, in turn, is used to understand some weaknesses of the current design spectra. Our velocity model, while regionalized and somewhatad hoc, is consistent with geophysical observations and the local geology. In the 0.02–0.1 Hz band, this model is validated by using it to calculate moment tensor solutions of 20 earthquakes (5.6 ≥ MW ≥ 3.2) in the 2012 Ferrara, Italy, seismic sequence. The seismic spectra observed for the relatively small main shock significantly exceeded the design spectra to be used in the area for critical structures. Observations and synthetics reveal that the ground motions are dominated by long‐duration surface waves, which, apparently, the design codes do not adequately anticipate. In light of our results, the present seismic hazard assessment in the entire Pianura Padana, including the city of Milan, needs to be re‐evaluated. Key Points Severe and widespread damage produced by relatively small earthquakes Long durations affect the ground motion in the Pianura Padana Only regional GMPEs correctly contribute to seismic hazard in Pianura Padana

Questo contributo risponde ai commenti e alle critiche al mio libro L’asino e il battello da parte di Fabio Saggioro, Andrea Augenti, Philippe Sénac, Giuseppe Petralia e Sergio Tognetti. Il testo intende sviluppare la discussione, tra gli altri temi, sull’uso dei dati archeologici per la storia economica e sulle principali linee di sviluppo economico medievale.