The first contact of the prehistoric inhabitants of the Aegean area with the area of the northern shores of the Black Sea (Euxenian Pontus) and the Sea of Azov (Lake Maeotis) must have taken place before the Younger Dryas (12,500–11,400) cold period. Then a long time followed in which we do not have any reference from the Greek mythology that the prehistoric inhabitants of the Aegean and Circum-Aegean region had contacts with the inhabitants of the European area. At the beginning of the second millennium BC, however, according to the archeological findings in southeastern Sweden and petroglyphs in Norway, it seems that Minoan traders must have been there. Since then, the Hyperboreans initially, and later the Mycenaean Greeks then, the Argonauts, Herakles, and many others must had developed these contacts, which initially were commercial, and in general only economic, while later they must had developed cultural relationships as well. It should be noted that communication was being made by ships through the large rivers, which, with the improvement of the climatic conditions, observed after the Younger Dryas period, were all navigable during the warm months of the year.