The 20-29 May 2012 earthquake events occurred along Emilia Romagna segment of Po Plain valley (Pianura Padana), a NW – SE oriented basin along the Southern tectonic boundary of Adria plate, with Northern Apennines. Major earthquake sequence events' focal mechanisms, evince the activation of low angle thrust structures, separating the earthquake activity on at least 2 distinct fault planes, with similar slip characteristics. Both planes seem to be on the same seismogenic source, on the Western part of 1570 events' source, interpreting the delimitation of the seismic activity of the May – June 2012 earthquake sequence. Widely observed secondary effects were categorized with respect to spatial distribution, density and trend, to: i) individual liquefaction cases, ii)Strictly oriented liquefactions and lateral spreading due to exposure of unconformities to surfacial liquefaction-prone geological formations and iii) extended liquefactions of confined liquefiable formations (at a depth of≈10m) and lateral spreading along river strike. This depth resulted in less surfacial deformation and differential subsidence, as well as very limited structural damage. Only fences, pavements and other light weight structures have been heavily damaged, deformed and dislodged. The incurred structural damage is extremely heavy for the churches and the cultural heritage, as well as for the industrial infrastucture of the region, besides the death toll and injuries. The available strong motion records are not adequate in order to explain in a rational and reliable way the above mentioned heavy damage. Based on years' experience in post earthquake investigations and on results of numerous full scale tests of structures on shaking tables, the authors concluded that the main reasons of the damage is the extremely high vertical ground shaking (of the order of 1.0 g) in combination with the moderate horizontal motions. Due to this very high value of the vertical ground shaking, impact phenomena are observed as well as total or partial loss of friction (due to the loss of gravitational forces).The incurred damage are grouped in general categories possessing similar characteristics. The majority of the observed damage of churches is mainly due to collapse of their roofing systems. This occurred due to resonance-like vertical vibration of the timber trusses of the roofs. This was proved by analysing representative dimensions of timber trusses with the overburden mass and, it was found that their fundamental periods are between 0.06 and 0.10 sec. On the other hand, a predominant period of the vertical component is, according to the recorded first event of 20th May 2012, 0.06 to 0.07 sec. Thus, intensive up and down motions are induced in the whole trusses and in their horizontal lower beams resulting in dislocations from their supports on the walls. On the other hand, it is well known that the arrival time between P (vertical) and S (horizontal) waves in epicentral regions is quite small. This resulted in a convolution between vertical and horizontal ground motions. The top of the walls, where are the supports of the trusses, were significantly displaced as free standing vertical cantilevers due to the loss of connection with the truss. In this way the trusses totally lost their supports and collapsed. In examining the debris one may guess what structure between the two (truss or wall) collapsed first. A proof of the dominance of the vertical component might be based, among others, on the response of bell towers that in the majority of the cases were not significantly damaged and on the fact that the mode of collapse is inside the ground plan of the building. Quite similar observations are also valid for the damaged industrial facilities.The natural vertical periods of the roofs are also, between 0.06 and 0.10 sec. The constructed supports are from functional point of view quite similar to those used for the support of the timber trusses in the churches (just simply supported cantilevers). Nevertheless, by using the conventional bolts in the supports, it is not certain whether or not the situation would be ameliorated. In order to prevent the effects of the high frequency impact type of the vertical ground motion a kind of absorbing elastomeric devices could be used in the supports of beams and trusses besides the conventional anchoring systems. Also, a kind of base isolation devices, that should not depend on friction at the base of the structures might be used. Finally, the partial collapse of the ceramic factory is attributed to the rhythmic phenomena of destruction. After the present communication was completed, it has just been released the important and technically very interesting vertical strong motion record of the second event, presenting a peak ground acceleration of the order of 0.9 g, a fact that comes in full agreement with the findings and arguments exposed in the present paper.