Evaluation of components and distribution area of ​​Yaz-I-III culture in northeastern Iran with emphasis on Khorasan cultural area

After the developments of the new Bronze Age on the Iranian plateau, a new era called the Iron Age emerged. Iron Age cultures of the northeastern region of Iran are completely different from the evolutionary theories and characteristics of the Iron Age culture of northwestern Iran, as well as the evolutionary approaches of this period in other cultural parts of the Iranian plateau. The Iron Age cultures of northeastern Iran, especially Khorasan, include two completely different cultures in terms of cultural materials and biological structures, which are called Yaz and Dahestan cultures. In the present study, in addition to describing the components of the two cultural systems of Yaz and Dahistan, we first try to explain the spheres of influence and common boundaries of these two cultural systems and then, accordingto recent studies, the biological structures of the Iron Age culture in Khorasan. Finally, an attempt is made to study and interpret the components of Yaz culture in relation to the traditions of the New Bronze Age as well as the Achaemenid period. The results of the study indicate the influence of Yaz culture in East Khorasan and Dahistan culture in West Khorasan to Gorgan plain. According to recent studies and current knowledge, Bojnourd plain in Atrak basin and Jajarm plain in Kalshour basin are the common borders of these two cultures (in North Khorasan province). In East Khorasan, the components of the Iron Age culture are closely related to the Yaz culture in Central Asia, and some local components are also evident. In addition, Yaz III period coincides with the Achaemenid period, which is ignored in the Yaz time division, which according to the types of pottery, to some extent can be traced to the components of the Achaemenid period in Khorasan.