Analysis of the Communicational and Functional Structure of Chiabour Site: A Residence from Partho-Sassanid Periods in Romeshgan Plain, Lorestan

Chiabour site is located in the center part of Romeshgan plain in the west of lorestan province. This site consists of a large mound (that called Chiabour) and some small settlements around it that their total area is 150 hectares. According to the location of this settlement in the whole area and their distance from ache other once could say that they formed a large site in terms of chronology and special relationship. This article aims to recognize the structural correlation and functional role between different parts of this site. The approach article is descriptive-analytical and its data collected through fieldwork survey and documentary studies. Results indicate that Chiabour site combined of a central settlement, an industrial section and some military structures around them that was established during the Parthian period and was used until the late Sassanid era. The large extent of Chiabour along verity of its cultural findings such as ceramics, stone objects and base of broken columns show that Chiabour mound has been governing seat and central part of the site. This central section has been protected by three military buildings; Tolle Khandaghe Mamejo in the southwest, Khandage Rashi in the south and Kandaghe Elfat in the north. Grill slags on the surface of Dargawah mound in the east of the site shows that it was the industrial area of the site.
Keywords: Partho-Sassanid, Roumeshgan, Chiabour, Communicational and Functional Structure.
 
Introduction
The Romeshgan plain, with an area of 33,000 hectares, is located in the west of Lorestan province. Features such as sedimentary soil with good rainfall (450 mm per year), sufficient water resources and rich pastures have made Romeshgan prone to agricultural and livestock activities in allperiod. In addition to environmental factors, the geographical capability of the Romeshgan Plain should be noted in that it is located alongside of the communication routes from south to northwest Iran and Mesopotamia and vice versa. These factors have led to the formation of numerous and important human communities in the Romeshgan. One of the most significant and important of these sites is the Chiabur site, which is located in the center of the plain and between the mountains of Mahla and Baraftao. The cultural materials collected from the surface of this site indicate the settlement stages of the late chalcolithic, Bronze, Parthian, Sassanid and Islamic periods. The available evidence shows that the most important settlement periods of this area were related to the Parthian and Sassanid periods. This vast site consists of several hills including Chiabur, Tale Khandagh Elfat, Tale Khandagh Rashi, Tale Khandagh Mammejo, Dargava Hill, Kaleke Maliki and Ganelsu Hill.
 In previous studies and researches, each of them has been studied separately. While the position of these sites relative to each other, their close distance, the pattern of distribution and closeness of their cultural materials in term of date show their connection. Given this, the main question is: what is the structural and functional relationship between the different parts of the Chiabur site, and what is the role and position of each of these components in the area? In order to answer the above question, the following hypothesis was considered: Chiabour site in Parthian-Sassanid periods consists of a central area with a number of military structures and an industrial sector. The aim of the present study is to introduce Chiabour area as one of the largest settlements of Parthian and Sassanid periods in western Lorestan and to determine the position and role of each component of this area and how they are related to each other. Introducing and studying this area, while introducing an important site of Parthian and Sassanid periods in the west of Lorestan, will be a step towards better understanding and explaining the position of Romeshgan region in Parthian and Sassanid governments.
 
Discussion
Chiabour’s parts are a short distance apart, and there are many similarities between the pottery pieces and their architectural remains. Most of the pottery collected on the surface of these sites consists of pottery belonging to the Parthian and Sassanid periods. This could suggest that the sites have had a lot of connection in the historical period and form a single site that each of them had a special function and role in the texture of the site. Due to the large area and location of Chiabour hill, the type, amount and distribution of its cultural materials this site can be placed in the center of the surrounding areas and can be defined a role such as the central area in relation to other areas for it. One of the closest areas to the main prominence of Chiabur Hill is Dargaveh Hill, located 800 meters southeast of it. Due to unauthorized excavations on the site have revealed possible evidence of industrial activity (furnaces). Evidence on the surface of the compound, including the presence of a furnace weld and part of the molten wall, indicates the presence of a pottery furnace located in areas close to the surface. In the northern, southern and eastern parts of Chiabour Hill, there are the Alft, Rashi and Mammejo moats, respectively. Geometrically, these ditches are quadrangular structures around which a pit has been dug. Their structural elements include a rectangular interior space with an embankment and a pit around it. Their average area is about 1.5 hectares and height between 2 and 3 meters above the surrounding land. There is no evidence of defensive fortifications including the castle or the tower around the Chiabour hill. In this case, the ditches around this site could serve as security and defense structures, protecting residents from possible dangers and attacks.
 
Conclusion
The Chiabour site with an area of more than 150 hectares, is formed from a large hill of the same name, the three ditches of Mamjoo, Ulfat and Rashi, as well as three hills with the names of Ganelso, Dargaveh and Kalk Mahki. These hills and ridges were probably different parts of a large settlement and each of them has its own functional role according to their position in the area. At the center of this area is Chiabour Hill, which is more important than other parts of the area, both in terms of size and cultural finds, including architecture, pottery, and stone objects. Architectural evidence on Chiabur Hill suggests the possible erection of a large, columned building that demonstrates the importance of the hill in the structure and texture of the Chiabur complex. Due to the importance of this hill, its location in the center of the Romeshgan plain and its vicinity to the communication routes and the absence of any fortifications and defensive walls around it, the three ditches on its northern, southern and eastern sides as military and defense structures, are supposed to provide security for residents against possible attacks and dangers. The presence of a pottery kiln on the surface of Dargaveh hill indicates the industrial activities inside this area.