(a) Geological map of the Montagna dei Fiori structure (modified from Mattei, 1987; Calamita et al., 2011). (b) Panoramic view of the Montagna dei Fiori fault along the forelimb/hinge zone of the anticline, showing the attitude of the footwall strata characterized by 30−40° dip towards the NE. (c) Geological cross-section (trace B-B’ in Fig. 4a). (d) Speculative template showing the interpretation of the Montagna dei Fiori Fault as a syn-orogenic, pre-thrusting normal fault (Calamita et al., 1998; Scisciani et al., 2001). (e) Speculative template showing the interpretation of the Montagna dei Fiori Fault as a NE-directed, high-angle upthrust (DUT) developed during the latest Cretaceous–Middle Miocene time interval (Calamita et al., 2021). Note that the cross-section (c) does not balance, due to the paucity of data to constrain its deeper parts, which prevents its quantitative restoration; however, it is presented here with the only purpose of illustrating the alternative, qualitative interpretations given for the same structure, the Montagna dei Fiori Fault, as a pre-thrusting normal fault (d) or as a West-directed upthust (e). One slightly different, third interpretation for the Montagna dei Fiori Fault, that is yet geometrically and kinematically consistent with the hypothesis of a pre-thrusting normal fault illustrated in Figure 4d, is that this tructure could represent the relicts of a supradetachment fault (terminology after Milia & Torrente, 2015), inherited during the episodes of extension that have accompanied the opening of the Tyrrhenian Sea and preceeded the upward-propagation of the Montagna dei Fiori Thrust (see the text for explanation).