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with the highest moment rate in the entire Mediterranean, at the southern part of Palliki peninsula. The sequence continued with numerous aftershocks that in the first few hours covered an area extended over 35 km, much longer than expected from the causative fault segment. Intense seismicity encompassing a major aftershock (Mw 5.5) in less than 6 hours after and several M>4.0 earthquakes mostly during the first three days, continued along the entire activated area, evidencing a less densely covered part where the second main shock (Mw6.0) on 3 February occurred, associated with the adjacent fault segment, located to the north of the firstly failed segment and evidently encouraged by stress transfer of the first main shock. The aftershock distribution evidenced two adjacent fault segments striking almost N–S and dipping to the east, in full agreement with the centroid moment tensor solutions, constituting segments of the Kefalonia Transform Fault (KTF). Intense aftershock activity lasted for several weeks whereas continued seismicity afterwards is mainly located off fault with minor and fewer on fault aftershocks. The seismic network was intensified in the area (Institute of Geodynamics portable network, seismic stations installed in the frame of OTRIONS project, CEN–ION network) after the main ruptures, providing improvement both in detectability and accurate locations. Since network coverage was not previously adequate for revealing detailed features of the activated area, the improved monitoring and location is of paramount importance for this scope. More recent seismicity, forming distinctive clusters, occurred along the edges of the double rupture indicatin