Papers given on a seminar celebrating the 25 years anniversary of the Petras excavations. Petras in western Crete was the site of a Minoan settlement. Despite the evidence for habitation in the last phase of the Neolithic period (3500 B.C.), the first settlement is dated to the Early Minoan II period (2600-2300 B.C.). It continued to be inhabited until 1450 B.C., when it was destroyed, along with the other Minoan centres. A short reoccupation occurred during the Late Minoan III period (1400-1300 B.C.). The settlement flourished in the Old Palace period (2000-1650 B.C.), when the central building of palatial character was built on the top of the hill; it reached a peak, however, in the New Palace period (2000-1450 B.C.) when many alterations of the buildings took place. In the 12th-13th centuries A.D. the top of the hill was occupied by a cemetery, of which 32 graves have been excavated.