Abstract
From the end of the Late Bronze Age and the beginning of the Iron Age, the eastern regions of northwestern Iran were involved in a series of large-scale ethnic migrations, the scope of which had previously extended to the Caucasus. Crossings in the Caucasus Mountains led these migrations to the Meshginshahr and Ardabil plains and the high and green areas of Savalan Mountain. Undoubtedly, nomadic immigrants, during several centuries of migration along the routes, had found a series of low-risk and easy-to-reach routes in which they traveled constantly. The constant traffic along this route has left countless cemeteries along with it. Today, the Shahsevan tribes of Ardabil province inherit some of these ancient routes and use them regularly. The adaptation of the routes of the Shahsevan tribes to the linear distribution of the Iron age sites on them, proves such a hypothesis. In the present study, which has been carried out by field studies with an ethnographic approach in the western parts of Meshginshahr plain and the western and northwestern slopes of Savalan Mountain, why and how to conformity of the ancient routes of the nomadic tribes of the Iron Age with the Shasevan tribe routes have been discussed. Extent of Iron Age sites located in the route of Shahsevan tribes, how the sites are distributed in the summer places of the western slopes of Savalan and determining the most important and main ancient migration routes based on the distribution of the sites and their extent is another issue that has been addressed in this research. The results of reviewing and analyzing the available data show the complete compliance of the Iron Age sites with the longitudinal line of the migration routes of Shahsevan nomadic tribes. Most of the identified sites along the routes are of the cemetery type, which are much larger in summer areas than other places.
Keywords: The Western Basin of Meshginshahr, Iron Age, Ethniarchaeology, Iron Age Migration Routes, Shahvevan Tribes.

Introduction
According to the studies in the northeastern half of northwestern Iran, ethnic migration to the plains of Meshginshahr and Ardabil intensified from about the beginning to the second half of the second millennium B.C, shortly before the beginning of the Iron Age; The existence of large central castles and small satellites, as well as the numerous cemeteries that exist in this area, most of which are unrelated to the settlements, is a reason for this. It is not clear what the reasons for these sudden and mass migrations and the human factors or geographical conditions involved were, but what is clear from archaeological evidence is the existence of a north-south migration line from the Caucasus towards the southern parts of Moghan plain, Meshginshahr plain and the northern parts of Ardabil plain. In the Meshginshahr plain, the areas around the foothills of Savalan have received so much attention that many of these nomadic tribes migrated to these areas and many others for whom sufficient resources were not available went to the Sarab, Mehraban areas. And the eastern regions of East Azerbaijan province, as well as the northern regions, have moved rapidly. In addition to archaeological studies, one of the best methods for identifying and studying the routes used by the Iron Age migratory tribes in the Meshginshahr plain is study the routes that use present or in a few centuries. In this plain of Shahsevan tribes, a clear example today is the same immigrant tribes that passed through this area several thousand years ago; Some of them have chosen temporary accommodation and others have been forced to migrate to better places. The Shahsevan are one of the most important nomadic tribes in Iran who have preserved many of their ancient traditions. These nomadic tribes are a living example of a dead tissue, tribes that in today’s machine world, like their ancestors, have maintained their nomadic way of life; In the cold season, they descend from the green slopes of Savalan and live in local winters or in their villages, and again in the summer season, they start moving towards the summer. The adaptation of the modern routes of these tribes to the distribution of Iron Age sites is an important point; That is, the Shahsevan use the same ancient tribes in most cases. Of course, there may be small changes in the path, which may be due to inevitable geographical and human factors.

Discussion 
So far, there has been no research on the origin of the ancient roads of Savalan Mountain or their distribution. The present study was carried out by conducting an extensive field study in the western basin of Meshginshahr plain, northwestern, western and northward slopes of Savalan Mountain. The area in which the field survey was conducted covers an area of 980 square kilometers. According to the studies conducted in the present study and field visits to all modern settlements that have been studied in the area, there were 5 main roads for the migration of Shahsevan nomads in this area. Although these routes are no longer used and transportation is done by vehicles, the traces of all these routes and even their old titles have been preserved. According to indigenous peoples, herds of cows, goats, and sheep passed through and around the villages, along with camels carrying the necessities of life. The first route starts from the border area between Meshginshahr and Ahar and the confluence of Qarasu with Ahar Chay, and the other routes located differently in the eastern regions, respectively. Among these routes, the longest route is way No. 4. It should be noted that in all these roads, the nomads, after entering the wide bed of Qarasu river, migrated there and after resting and watering the cattle, they moved to the foothills of Savalan; These routes are selected in such a way that they cross several important rivers and in some of them they rested temporarily, such as Qarasu, Khiavchai, Meshginchai, Habashichay and Aharchay. The nomads crossed at least two or three of these rivers in each of these five routes. In general, 207 ancient sites were recorded along these 5 main roads that lead the Shahsevan nomads to the slopes of Savalan, which indicates that these routes were also used by the nomadic tribes of the Iron Age. The number of 181 sites (87%) are the cemetery types, which, are unrelated to the settlement sites and clearly belong to the Iron Age nomadic tribes. Almost half of the cemeteries are located in the slopes of Savalan, in the present summer tents of the Shahsevan tribes. Other registered sites are the central and satellite castles and settlement sites, all of which without exception were in the plains and along the route, and no traces of this type of sites were seen on the slopes. About 31% of the sites have an extent between 1 and 2 hectares. 25% of them have an extent in about 0.5 to 1 hectare and about 21% of the sites have an extent in about 2 to 4 hectares. 

Conclusion
Undoubtedly, the establishment of a route as an easy access route for migration has taken place over several centuries and millennia. The routes that were constantly traveled and based on experience, their quality have been tested for a long time and the most appropriate ones have been selected in terms of life and financial security. Looking at the general map of all the routes and the distribution of the Iron Age sites, the location of these sites on the route of these roads is quite evident. As you advance from the paths to the sides, the number of the sites decreases. This way of distribution of the sites shows that the sites are in a longitudinal line, and this longitudinal line is the route of modern and ancient roads. Examining the roads of this field contains other points. In all the routes, as much as possible, moving inside the valleys and next to the cliffs and slopes has been avoided. Only in the cases where they had to enter the river bed to rest and water the cattle, longitudinal movement along the path and inside the river bed was avoided, and entering the river bed only vertically have taken place to pass through. In all the routes, until reaching the low and steep slopes of Savalan, continuous movement has been made on the level of the plain and areas that have a full view of the surrounding environment. It seems that this was done to ward off possible natural, animal and human dangers. In general, the following can be obtained from the present study: Today’s routes are in line with the distribution of Iron Age sites; Most of the Iron Age sites located in the path and summer places of Savalan slopes are of the cemetery type; The located in the summer area and between them are more extensive; Many routes are interconnected and it was possible to change the route in all of them easily; Towards higher slopes, the number of ancient sites has been significantly reduced; Both along the route and in the summer places, the density of areas near and where water sources are much higher; In summer places, concentrated cemeteries or the accumulation of large graves in a small area, is rarely seen and many cemeteries, despite their large area, have low grave densities. The graves are scattered at a distance from the summers and their distance.