Callatis Ancient City was built, according to ancient sources, at the end of 6th Century B.C. Dorian colonists from Heraclea Pontica. The city was built upon a demand of an oracle, on the remains of a Getic settlement named Cerbatis or Acervetis. The ancient city was documented by many ancient writers, such as Ptolemy, Strabo, Memnon, and Ovid, Pliny the Elder, Arian, Pseudo-Scymnus, Demetrios of Callatis and Scylax of Cariadna. Pseudo-Scymnus wrote that “Callatis City rose like a Heracleotic colony, at the demand of an oracle; they built it when Amyntas rules over Macedonia”. Demetrios of Callatis wrote 20 volumes in which he reminds about the heracleotis origin of Callatida, the command of Deplhi oracle, the basis for building the city and the date is the beginning of King Amyntas’ reign. The epigraphic inscriptions discovered at Mangalia strengthen the hypothesis the ancient city of Callatis was built according to the oracle in Delphi. Although ancient writers place the founding of Callatis at the end of 6th century B.C., the oldest archaeological proofs are from the 4th century B.C.- indeed, in the 4th century B.C., the city reaches a great development and it is then when the defensive wall is built.