Abstract
Mehr-Narseh is known as one of the most important character of the middle Sassanid era. Based on the written historical sources, the construction of some buildings has been attributed to him, among which the most outstanding ones are five fire-temple monuments built in the southwest of Fars. Although various theories have been put forward regarding the location of the structures, by far, the nature and qualitative value of them are unknown. In this study firstly, the political-religious personality of this Sassanid minister in various ways was investigated, then besides recognizing their religious nature and value via analysis of the sources related to Mehr-Narseh fire temples, the Chahar-Taqis attributed to him was also studied, according to the current theories,  so as to reveal some features of  the religious architecture of Sassanid era. This is a fundamental or basic research, and the nature and method of which is historical and descriptive-analytical. The data is also collected from library and fieldwork. Based on the results of this study, it seems that the fire temples built by Mehr-Narseh included two separate types and four fire temples attriuted to him located in Abruwān area were related to family fire meaned “Dādgāh”. According to the field studies and similarity, the previous theories can be criticized and a new group of religious temple of Sasanian period in Farashband can be introduced that contains one or several fire temples, which are attributed to Mehr-Narseh. It seems that these kinds of fire temples have a complex plan with additional architectural and probably had a number of attendants to do the work related to the fire temple. Overall, this research can provide a correct understanding of the fire temples of “Dādgāh” Fire during the Sassanid period. This also provides a new grouping manner for such these temples and can be known as a pattern for reviewing of usage and religious value of other similar Chahar-Taqis.
Keywords: Mehr-Narseh, Fire Temple, Chahar-Taqi, Sassanid Era, Dādgāh Fire, Farashband.

Introduction
One of the important points mentioned in the historical resources is the information regarding the personality of Mehr-Narseh, as one of the significant figures of the middle Sassanid period, who built several fire temples and made other services in several other fire temples, which has been attributed to him by the order of the Sassanid emperors. Discovering the fire temples constructed under the order of Mehr-Narseh has been one of the most interesting study topics related to the religious architectures of the Sassanid period during the last century. There are different theories regarding the probable location of the fire temples attributed to Mehr-Narseh, which mainly include the region between the current Kazerun, Farashband, Dehram, and Firouzabad. This article attempts to study the fire temples attributed to Mehr-Narseh from a different perspective. In the first step, we study and explore Mehr-Narseh character to determine his political position in the middle of the Sassanid period and have an idea of his religious position in the system. The second step is to survey the nature and characters of the fire temples attributed to him from in terms of the quality value and their positions, to have a final analysis of their architectural complexities. The main question of this study is the religious quality of the fire temples attributed to Mehr-Narseh and what kind of fire was kept in the fire temples attributed to him? Also, based on the fires kept in these fire temples, what is the level of architectural complexity of the mentioned structures? The proposed hypothesis for this question is that it is possible that the four fire temples of Mehr-Narseh were containing the fire of “Dādgāh” and the fire temple of Jereh contained the fire of Ādarān. It is also assumed that the Dādgāh fore temples of Mehr-Narseh had additional spaces in the form of small architectural complexes. Based on the purpose of the study, this is basic research and from the perspective of nature and methodology, the study is conducted via the historical and descriptive-analytical method. The data collection method was library study and fieldwork. Initially, the political and religious figure of  Mehr-Narseh was analyzed and studied, with the help of the written sources related to him or the fire temples attributed to him, to reach understanding about the nature of his fire temples through a comparison between his character and the characteristics of the fire temples attributed to him. The next step was the archeological surveys in the fieldwork alongside the library researches and evaluating the archeological documents and reports about the proposed Chahar-Taqs for the location of the fire temples attributed to Mehr-Narseh, from an architectural perspective to finally reach a suitable point of view about the architectural and religious quality of the fire temples attributed to Mehr-Narseh.

Discussion
According to Pahlavi and Islamic sources, Mehr-Narseh, the minister of the Middle Sassanid period, has attained his highest religious official during the reign of Bahram V, as the honored titles of the servant of the two fire temples, since in the “Matigan-i Hazar Datistan” there is no mention of him being resented by Bahram V. During the reign of Yazdgerd II and Pirouz, he and his wife were sentenced to be the “Ādurwaxšīh” or tending the fire of the temple fire, due to a sin that some researchers associated with Zurvanism. The religious dedication of Mehr-Narseh resulted in the construction of several public buildings in the provinces of Ardashir-Khwarrah and Shapur –Khwarrah and also four religious temples on his ancestral lands for himself and his three sons, which were run by his heirs until the first centuries of Islamic period; these fire temples were shires dedicated to the “Atash-e Dadgah”. Based on the archeological findings and the presented theories, the remains of the three Chahar-Taq of “Malik”, “Tall-i Djangi”, and “Khurma yak” can be identical with one of the four fire temples belonging to Mehr-Narseh, as well as to match the information provided in written historical sources. Meanwhile, the site of “Pir-e Jeyran” may also be considered as the fourth fire temple of Mehr-Narseh in Abruwān. Based on the comparison studies of the archaeological evidence and the written sources, it can be concluded that during the Sassanid period, the shrines associated with the fire Dādgāh, could be very magnificent according to the financial conditions and social status of its founder and have donations such as gardens and farmland, and their revenues were spent for the happiness of the soul of the founder. Such fire temples were also run by a person named “Sallar” or the guardian who was chosen by the founder of the fire temple, and this responsibility was transferable to their heirs. The existence of such a title could indicate that other people also served in these private fire temples, and therefore this category of family fire temples, like the fire temples associated with the “Behrām” and “Ādarān” fires, could have hierarchical complexities in terms of the number of servers.

Conclusion
Based on the results of this study, it seems that the fire temples built by Mehr-Narseh included two separate types and four fire temples attriuted to him located in Abruwān area were related to family fire meaned “Dādgāh”. According to the field studies and similarity, the previous theories can be criticized and a new group of religious temple of Sasanian period in Farashband can be introduced that contains one or several fire temples, which are attributed to Mehr-Narseh. It seems that these kinds of fire temples have a complex plan with additional architectural and probably had a number of attendants to do the work related to the fire temple. Overall, this research can provide a correct understanding of the fire temples of “Dādgāh” Fire during the Sassanid period. This also provides a new grouping manner for such these temples and can be known as a pattern for reviewing of usage and religious value of other similar Chahar-Taqis. Before this, no specific structure for the fire temples related to the fire of “Dādgāh” in the Sassanid period, had been introduced, and the only available evidence was about the findings in “Tull-i Sifidak” which has a cruciform architectural space beside the residential context, as a sacred place for the fire. Based on conducted analyses of this study, it is possible to categorize the different types of religious architectural structures dedicated to the fire of “Dādgāh” into two groups: The first type was the buildings that include a cruciferous space attached to their residential section, that might have simpler procedures and endowments. The second type was complexes including Chahar-Taq and interconnected architectural spaces, which were probably built in the endowed properties of the fire temple, including gardens and agricultural lands, and belonged to people with high social ranks in the Sassanid society, such as Mehr-Narseh fire temples.