Studying various aspects of the Iron Age culture of Eastern Iran and Khorasan based on comparative studies is one of the most important challenges of the Iron Age. In the current situation, the components and features of the Northeast Iron Age, focusing on Khorasan, due to lack of studies, have remained largely unknown and ambiguous, and the need for purposeful studies is strongly felt. Now, based on few studies and excavations in Khorasan, little evidence of Iron Age cultures has been identified and measured in a comparative approach with the important cultures of Central Asia (Yaz and Dahistan). Accordingly, in the Gonabad plain, which is located almost in the south of Khorasan and is limited to the Ghohestan cultural area, the Hesare Omrani site can provide basic information about the Iron Age of Khorasan. The Hesare Omrani, which is located close to the current city of Gonabad, has a main ridge that can be seen with a diameter of more than 800 meters, the distribution of cultural materials around it. Due to the vastness of the area in this study, by adopting a methodical surface study, cultural materials, which are mainly pottery, have been collected and interpreted in the form of Early to Late Iron Age cultures. The results of studies show that the clay traditions of the Hesare Omrani have a significant affinity with Yaz culture and its pottery species can be analyzed in the framework of Yaz culture I to III. This site has handpainted pottery of the early Iron Age and simple forms of wheel-making pottery of the Middle and Late Iron Ages. In addition, the settlement landscape alongside the current status of the remaining deposits in the context of Central Asian experiences shows human communities with a settlement and social pattern similar to its Iron Age.

Khorasan’s Iron Age differs significantly from the Iron Age elements found in western Iran. In terms of cultural aspects and life structures, this encompasses two distinct cultures known as Yaz and Dahistan in classic classifications. Such definitions, which Russian archaeologists introduced to archaeological literature, have been heavily criticized. This is because the 8th and 7th centuries BCE, 550-300 BCE, and 330-217 BCE, which corresponded with the Medes, Achaemenid, and Seleucid Empires, were overlooked. Accordingly, the primary goal of the research was to investigate the political positions of the aforementioned empires in the region during the Iron Age. However, data collected about the Achaemenid and Hellenistic eras, as well as documented sources, have frequently mentioned the Satraps of these two empires in northeast Iran. The majority of cultural material on this region has been introduced based on the first millennium BCE, but this study took a political sociology approach to present new suggestions in the chronology of Khorasan’s Iron Age. Having said that, social developments in Khorasan from the Late Bronze Age to the establishment of ruling dynasties have been overlooked. According to chronology, the pre-Median, Median, post-Median, Achaemenid, and Seleucid eras all fall within the Iron Age period, and it is suggested that they be included in the region’s political history

The Khorasan region, especially the Kashafrud basin, has culturally retained a strategic position by virtue of its location between three major cultural spheres of southwestern Central Asia, the Central Plateau of Iran, and northeastern Iran. The Iron Age still remains a mainly unknown period in this region. In northeast Iran, particularly in the Greater Khorasan, the period is characterized by cultural attributes utterly different from those of the other parts of the Iranian Plateau. Coeval archaeological evidence from Khorasan shows affinities with the Yaz and Dahistan cultures of Central Asia. The major topics considered in this study are: the distribution pattern and major influential factors in the formation of the Iron Age settlements in the Kashafrud basin (Mashhad Plain), the nature of Iron Age cultural material in the region, and the characteristics shared between the contemporary settlements in Mashhad and the adjacent regions. Further major research objectives include proposing a comparative chronology, analyzing the regional cultural landscape, and specifying the Iron Age settlement patterns in the region. Thus, attempts have been made to answer the research questions through ArcGIS maps, analysis of surface ceramics, and the landscape archaeology approach. The results indicate the impressive role of environmental factors, especially the Kashafrud River as the leading regional resource, in the advent of Iron Age settlements. Moreover, the regional material culture exhibits strong affinities with the Iron Age culture of “Yaz” in Central Asia, and indicates relations and population movements between the different regions that were under the influence of this culture.