The northern Apennines have been the object of numerous studies, both from a morphological and a structural point of view. At present, much debate is going on about the existence and interpretation of NE-SW alignments, described by geomorphologists [Boccaletti, M., Coli, M., Napoleone, G., 1977. Nuovi allineamenti strutturali da immagini Landsat e rapporti con I'attivita sismica negli Appennini. Bell. Sec. Geol. It. 96, 679-694; Signorini, R., 1953. Linee tettoniche trasversali nell'Appennino settentrionale. Rend. Acc. Naz. Lincei 6, 42-45] and partly denied by structural geologists. We show new microtectonic and morphological data which contribute to a more comprehensive interpretation of these elements. Stress axis determination and different morphotectonic analyses have been combined. The analysis of the drainage networks and of two different digital elevation models have also been considered. The results lead us to interpret the NE-SW alignments as large and diffuse deformation zones which may represent old transfer zones active with left lateral strike slip movements during the mountain building. (C) 1998 Elsevier Science B.V. All rights reserved.