Location of Ojan Ilkhanid City Based on Historical Resources and Archaeological Investigations (Research on Sites of Koller and Dali Darasi in Bostan Abad City)

The historical city of Ojan (current Bostan abad), is one of the Ilkhanid major cities (the summer residence of the Ilkhanid royal family) in the course of prosperity and development of Ghazan khan. According to sources, this history of the city dates back before Ilkhani era. However, as a consequence of various events such as earthquake and wars, its existence couldn’t be revealed as a strategically important city. It was until the Ilkhanid era when the importance of the city was unclosed. According to the shortage in sources about the exact location of this city, the necessity to study and scrutinize the remains of this city is highly required. Therefore our main question investigates the exact location and measures of the city in accordance with archaeological investigations and historical resources. Obtained architecture structures include battlement which are square shape, governmental castle, some monitoring turrets and terminated walls, incused under glaze clays, under glaze paintings and local clays without glaze belonging to 6th-8th century A.H. which are the monument of Ilkhani city of  Ojan according to picturers.
Considering the 3 chapters investigation on archaeology in Bostan abad town, there are achieved some results which are associated with Ojan city: 1- Existence of the city in the first centuries of Islamic and its development in the Ilkhanid era (documented in historical resources). 2- Adaptation of its geographical position with current Bostan abad city (documented in archaeology studies) in two Ilkhani sites of  Kollar and Dali darasi. Therefore, this paper has tries to analyze new obtained data from archaeological investigation in the region of Bostan abad with written resources of Ilkhanid era in order to take another step toward finding its precise location.
Considering government house, rabaz and sharestan, the wall has a circular shape. This section - cone-shaped hill with elliptical cross - is about 10 meters above the surrounding terrain. The remains of brick arched walls and stone can be seen in this section. Surface works show that the palace was probably in the south west of the castle (based on Chalabi’s painting is in the north west of castle) and it was a distance of approximately 100 meters from castle to inside of the wall. The place of sharestan and rabaz is out of identification bounds and agricultural activities and land leveling has destroyed this sector. Even current location of Ashraf abad’s village could be one of the assumptions of sharestan and rabaz’s position; and likely in the time of construction rural access roads, part of the area is turned into suburbs. Finally, it must be said that based on archaeological researches, the Ilkhanid city of Ojan must be sought near the present city and according to recent studies, the sites that having all this specifications are the two sites named Koller and Dali darasi which are the section of Ojan city. However, defining the exact geographic position and location of the city spaces and speeching area requires further speculation and ongoing archaeological investigations since the exact result cannot be announced according to the existing data. It is hoped that with the support of multilateral authorities this project will be fulfilled as soon as possible so that its achievements be useful for future researchers and archaeologist.