Abstract
Kohgiluyeh; One of the most enduring names of the Islamic era is in the southwestern part of Iran, which has played a very important role in the political and social changes in this region. More than a thousand years have passed since the name of Kuhgiluyeh was mentioned in historical sources, but so far there has been no mention of the existence of such a city and it has always been mentioned as a geographical area or region. Recent discoveries in the historic city of Dehdasht show that Kuhgiluyeh was not only a geographical area, but also the most important urban center of the region in the Islamic Middle Ages. Also, it was of great importance in politics, military, economics, and even religion. This evidence includes a valuable treasure of 194 historical coins, some of which have the city of Kohgiluyeh engraved on as the place of minting. The location of Kuhgiluyeh city among the mints of this period shows the importance and of this city, which has remained unknown until now, and its geographical location is not known. Now, these questions can be asked: During what period and at what time were they discovered coins minted? When and what time did the city of Kohgiluyeh mint on these coins? Where is it located today in terms of geographical location? Which of the historical sites of the region is it compatible with? This study aimed to determine the period of minting the discovered coins, to locate the geographical location of Kuhgiluyeh city, and to gain information about the method of collecting library and field information. Its approach is historical-analytical. Kuhgiluyeh Mint, as one of the most active and important mints in the period of Agh-e-Quyunlus and Atabakan Lor Bozorg, is in harmony with the historical city of Dehdasht, in Kohgiluyeh. The Safavid period was renamed the city of Dehdasht and over time, the name of Kohgiluyeh has been forgotten.
Keywords: Coin, Kuhgiluyeh Mint, Agh Quyunluha, Historical City of Dehdasht.

Introduction
Kuhgiluyeh is one of the most famous places in the southwest of Iran, which according to historical sources, its peak period and fame; Goes back to the Safavid period (Valeh Esfahani, 1993: 643; Mirk Hosseini, 2006: 437). Lack of information about this area has led many researchers to rely on new archaeological evidence and discoveries, especially written works and findings, for more information and knowledge of its dark and unknown aspects. The study of coins discovered in the historical city of Dehdasht has provided us with useful and important information about the political and economic situation of this region during the Agh Quyunlu period, the most important of which is the introduction of the city of Kuhgiluyeh as one of the most important mints of this period. Until now, there was no information or knowledge about it.  
Research Purpose: The aim of this study is to introduce and locate the city of Kuhgiluyeh in the Islamic Middle Ages, to study the discovered coins and to study and analyze the historical sources as well as the most important urban centers of the region. 
Research Questions: 1- What period do the coins discovered from the historical city of Dehdasht belong to and during which rulers were they minted? 2- The location of the historical city of Kuhgiluyeh corresponds to which of the historical sites? 
Research Method: This research has been conducted by descriptive-analytical method and its information has been collected through library and field studies. The field information of this research is based on the study of a collection of coins minted in Kuhgiluyeh, which was discovered in 2009 AD in the form of a small treasure consisting of 193 silver coins in the historical city of Dehdasht and is kept in the repository of the Archaeological Museum of Yasuj. 

Discussion
The most important collection of coins discovered in the city is a collection of 193 silver coins that was discovered in 2009 AD during the demolition and restoration of Pirghazi tomb in the portico of the historic city of Dehdasht, in Kohgiluyeh and Boyer-Ahmad provinces.  Studies on coins discovered in the historical city of Dehdasht, show that 80% of these coins are of the type of surcharge coins and the rest are of the type of common mint coins.  Coins discovered; they belong to the reign of the Turkomans of Aq Quyunlu and the reign of Ozun Hassan (1453-1477 AD) to Sultan Muhammad (1500 AD). According to studies, 14 coins from this collection were minted in Kuhgiluyeh Mint during the reign of three rulers of this period (Sultan Yaqub, Sultan Rostam, and Sultan Murad).
The total number of coins minted during the reign of Sultan Yaqub in this collection is eight coins; the place of minting two coins is Kuhgiluyeh. Out of 64 coins minted by Sultan Rostam (1484-1496), 11 coins are minted by Kuhgiluyeh. The number of coins related to the time of Sultan Murad (1497), are 19 pieces and all of them are without surcharge and are of the type of ordinary coins. Among these coins, one was minted in Kohgiluyeh. 
Before the Agh Quyunlu period, in the Atabakan Lor period, the name of Kuhgiluyeh was mentioned in the list of mints (Alaeddini, 2017: 181). The minting of several coins by the rulers of Aq Quyunlu, with the minting of Kuhgiluyeh, which is sometimes of high quality and weight among other mints of this period, shows that not only this city did not decline during the transition from Atabkan to Aq Quyunlu but has been able to maintain its past position, become one of the most active and important mints of this period. 

Conclusion
According to the studies conducted in the Giloyeh mountain region and its sphere of influence, only two cities, Behbahan and Dehdasht, have the necessary conditions and potential (area, communication and climatic location) to locate and propose as the location of the city of Koohgiluyeh. There is no doubt or ambiguity about the history of Behbahan name since its formation in the 14th century AD until today and in terms of its settlement history and naming can not be related to the city of Kuhgiluyeh which in the 14th century AD, due to the importance of the city, coins were minted. Therefore, the only historical site in the region that can be compared with the city of Kuhgiluyeh in terms of age and historical background, size and geographical location and climatic conditions, is the historical city of Dehdasht.  The study of archeological findings such as pottery discovered from the historical city of Dehdasht also dates the city back to the Sassanid period and early Islam.  In addition to archeological findings, historical sources in their descriptions of the historical city of Dehdasht refer to much older works outside the city walls and also the order to build the city of Balad Shapur by the second Sassanid Shapur, which is consistent with the results of archaeological findings, has it. The cities of Kuhgiluyeh (Islamic Middle Ages) and Dehdasht (Safavid period) have many commonalities, the most important of which are the antiquity of these two cities and the lack of historical information about their historical status in the pre-Safavid period and their location in a same geographical area, which can be the point of connection between the two.  According to what has been proposed so far, the city and mint of Kuhgiluyeh in the 14th and 15th centuries AD can be located in the current location of the historical city of Dehdasht in the city of Kuhgiluyeh.