The Second Palace period runs from the widespread destructions around 1700 bc, which bring an end to the Protopalatial period, to another major destruction horizon at the end of Late Minoan (LM) IB, c.1450 bc. The latter destructions, often accompanied by fire, have most often been attributed to war-like incursions linked to the arrival on Crete of Mycenaeans, but earthquakes could also have contributed. A combination of these two factors is probable, with natural disasters encouraging hostile actions. Most Cretan sites are then left in ruins, and notably the palaces of Malia, Phaistos, and Zakros definitively so. It is the end of the second palaces. In terms of relative chronology, the period covers both the end of the Middle Minoan (MM III) and the beginning of LM I.