The Kashafrud area has always been considered by many researchers due to the existence of works from the ancient Paleolithic period, as the oldest cultural area in Iran. For this reason, this cultural field is known in the archeology of the Iranian plateau and the Middle East and is a very important subject. Due to the heterogeneous and limited distribution of archaeological excavations in the territory of Khorasan, our knowledge of the prehistoric cultures of this region in all areas is unknown (Basafa & Rezaei 2014; Vahdati, 2016). In this study, by studying and analyzing the pottery traditions of Kashafrud basin, the relative chronology of settlements have been determined. And the dominant cultural styles of the region have been studied. In this regard, relative dating and compiling a chronological table is one of the archaeological necessities of this period. Assessment of prehistoric pottery cultures and evaluation of intra- and extra-regional interactions are research questions. So far, only two prehistoric review and identification projects have been carried out in the city of Mashhad, which include the study of the Kashafrud River by a joint Iranian-French delegation headed by Ali Ariaei and Claude Thibaut (Ariai and Thibault, 1977), and the survey of Mashhad city by Mahmoud Bakhtiari in 1998 (Labaf Khaniki, 1391). However, there are a few other scattered studies whose results have been published in several articles. However, several scattered studies have been conducted in this area that their results have been published in the form of several articles. Absolute and relative chronologies of the cultural regions of northeastern Iran and southern Turkmenistan have been used in the relative dating of cultural periods of the Kashafrud basin. However, generalizing these dates to surface materials without any stratigraphic study would be challenging. At present, the dates presented in the present study are based on a combination of chronologies presented in the northeastern regions of Iran and Turkmenistan, and its basis may be changed by future archaeological excavations in the Kashafrud basin. The basis of the statistical population of this study is the cultural materials of the Pottery Bank of the Greater Khorasan Museum, which were randomly sampled based on registered reports. An important point in the deployments of Kashafrud River is the relocation and collection of surface samples in the non-academic process.
The city of Mashhad as a main part of Khorasan Razavi province and is located between two mountain ranges. Its northern mountain range is a Hezar-Masjed and its southern mountain range is Binalood. A river called Kashafrud passes through this plain. This area is located in the geographical coordinates of 22-57 to 10-61 east longitude and 39-35 to 04-37 north latitude (Figure 1).
In total, and based on the studies conducted so far, about 14 prehistoric settlements have been identified within the city of Mashhad and in the Kashafrud basin (Figure 2), that four settlements of them have emerged for the first time in the Iron Age, which is out of this subject research.
In the other 10 settlements, they have cultural sequence from the Neolithic to the Bronze Age and in some continuities to the Iron Age. Of these 10 settlements, three settlements of Qaderabad, Qare Tappeh and Abarghandaray have a sequence from the Neolithic period (6500 BC according to the initial phase of Jaitun and not Sange-e Chakhmagh) to the end of the Bronze Age. In this research, the bronze period means only two phases, old and middle (equal to the date 2900-2100 BC according to the sequence of Namazgah Depe and up to 1700 BC according to the BMAC culture). According to material cultures, two Sites of Morghanoo and Naderi have appeared for the first time in the transition period from Neolithic to Chalcolithic (5000-4800 or 4500 BC according to southwest Turkmenistan chronology) and have a cultural sequence up to the Middle Bronze Age. Based on the available evidence and cultural materials from among these settlements, the Toup Derakht site has appeared for the first time in the Late Chalcolithic or Namazgah III (3500-3000 or 2900 BC depending on the sequence of the Namazgah). The establishment of the Toup Derakht has a cultural sequence until the Iron Age. The 4 Sites of Devin, Qalurkhaneh, Gash and Junow have appeared for the first time in the Bronze Age, only in which the Devin Tape and Gash Tape have a cultural sequence up to the Iron Age.
Based on the study, classification and typology of evidence of the studied area, it was found that the three settlements of Tape Qaderabad, Qara Tape and Abarghandaray Ancient Site have Neolithic surface materials that stone tools (Figure 3) and pottery with appearance characteristics and technically belongs to the Neolithic period (figure 4). The most important cultural materials belonging to the Neolithic period include buff and red ware with geometric designs. They are handmade and have chaff temper. In addition, those samples in terms of form, pattern and technique are comparable with Sang-e Chakhmagh, Jaitun and Neolithic of the Central Plateau of Iran (Table 2). Finally, according to the relative chronology, the date before 6500 BC to 5000 BC can be considered for the Neolithic period of Kashafrud basin. Based on the study of surface materials, the studied settlements of the transition period from Neolithic to Chalcolithic to the relative date of 5000-4500 or 5200-4800 BC have continued in three settlements of Tape Qaderabad, Qara Tape and Abarghandaray were formed for the first time in this period. The existence of cultural materials of the Chalcolithic period in the three settlements of Qaderabad, Abarghandaray and Qara Tape, equal to the date 4800-2900 BC, indicates the continuity of the establishment and cultural sequence from Late Neolithic period to the Chalcolithic. Also, the presence of surface cultural materials on the settlements of Tape Naderi and Morghanoo, which have appeared in the transition period from Neolithic to Chalcolithic period, has a sequence and continuity, and in addition, the Toup Derakht site also appears in the Late Chalcolithic Period. In addition to these cultural materials, the Early and Middle Bronze Ages have sequences in all the mentioned settlements, including Qaderabad, Abarghandaray, Qara Tape, Naderi, Morghanoo, Toup Derakht Sites, and in addition, Gash Tape, Qalurkhaneh Ancient Site, Tape Junow and they also settle in the Early Bronze phase for the first time. As a result, Kashafrud River, as a vital and effective factor in creating a fertile ecosystem, has provided a suitable platform for spatial and regional Choices of human societies from the Paleolithic period to the present, which in both material and immaterial dimensions with culture, Prehistoric regions of Northeast Iran, especially Shahroud and Damghan, Gorgan plain, Dargaz and Atrak basins, as well as prehistoric cultures of southern Turkmenistan, including the Neolithic period of Jaitun and Anu IA, culture Namazgah I - VI period It is an overlap and perhaps the Kashafrud basin can be considered as the link between the prehistoric cultures of southern Turkmenistan and the Iranian plateau, especially the northeastern region of Iran.