Abstract
Despite the importance, position and high role of the city of Hamadan in the political, economic, social and cultural developments of Iran during the Qajar era, targeted studies that determine the spatial organization and social structure of this city during that period have not been carried out, and there are many questions regarding the nature of the changes in the context. Its history remains unanswered. The current research seeks to answer questions about the transformation and development of the spatial structure of Hamedan city during the Qajar era by relying on written sources, architectural works and archaeological evidence. In order to achieve this goal, while using all the written sources related to this city in the mentioned period, the changes of the urban context and the structural characteristics of its spaces were determined and the factors affecting the growth and development of the city were determined during this period. The result of the research made it clear that due to its ancient background, special geographical location, benefiting from suitable environmental capabilities such as abundant water resources, and also due to its location on the path of important trade-pilgrimage routes in the Qajar period, Hamedan was one of the cities with social and economic importance and status. It has gained merit and accommodates a relatively large population and has attracted the attention of various social groups, especially merchants. Thus, suitable conditions have been created for the construction and discovery of numerous architectural works and monuments with different functions (defense facilities, residential neighborhoods, squares and plazas, markets and caravanserais, mosques, schools, baths, churches, etc.) and the urban space, especially in aspects The south and southeast have developed and expanded significantly.
Keywords: Iranian Cities, Qajar Era Cities, Historical Context of Hamadan, Spatial Structure, Written Sources.

Introduction
Cities are one of the main centers of the emergence of civilization and valuable cultural treasures, without knowing them, it is not possible to study the history of various developments in human life. For this purpose, the study of the cities left from the past plays a significant role in understanding the political, administrative, social, economic and cultural structure of the societies that created them (Krimian, 2014: 121-111) and can provide clear horizons in recognizing the physical, social and cultural structures And reopen the past civilizations to researchers (Krimian and Seyedin, 2009: 69). The study of the ancient living spaces of Iran and the historical contexts of the cities is a necessity that has allocated a part of the scientific activities of archaeologists. Although the historical fabric of Hamedan has suffered a lot of damage due to various reasons, including indiscriminate and irregular constructions, but a number of its historical and valuable buildings have survived the ravages of various times and manipulations. Recovered and recognized to a great extent. Hamadan is one of the few historical and ancient cities in the country that has survived historical developments with strength and has preserved its historical context to some extent. Undoubtedly, Hamedan’s location on the path of communication routes in different eras, as well as its special geographical location and the benefit of environmental capabilities are the main reasons for the continuity of this city throughout history. Fortunately, valuable elements of the architecture of the Qajar era have survived in this city, and by studying them, it is possible to analyze and restore the spatial structure of Hamadan city to a great extent.
The purpose of the Research: The main purpose of the research, the results of which are presented in this article, is to find out how the physical structure and spatial organization of Hamadan was created, developed and transformed by relying on architectural works, archaeological evidence, written sources and visual documents left from the Qajar period.
Research Questions: In this study, we have attempted to answer questions about space structure, different types of architectural works, scope and physical realm, as well as the extent to which different social groups have been influenced by the space organization and architectural works of Hamadan in the Qajar era.
Research Method: The study presented in this article is historical -analytical in nature and content, and has been conducted in both field and library methods.
The original text of the previous article consists of several different sections. In the discussion of the research background, the most important studies on the historical context of Hamadan have been emphasized with the emphasis on the Qajar era. In the context of the structural characteristics of the Iranian cities in the Qajar era, the main characteristics and components of the identity of Iranian cities in the Qajar period as well as how the structural characteristics of Iranian cities from the Safavid era to Qajar has been discussed. The next section of the article is analyzed and explained by the Qajar Space Organization in the Qajar era based on written sources. Travelogues and historical texts from the Qajar era have formed the most important study sources in this section. In the other section, the urban spaces of Hamadan during the Qajar period are discussed. In this section, relying on written sources and existing architectural evidence, some of the most important physical and historical spaces recovered by the Qajar era of Hamadan, including defense facilities, residential neighborhoods, inter -and -outskirts, squares and squares, commercial spaces and markets And the disposal of sewage, mosques, baths, churches, and so on. It was also known that marketers and traders were more involved in the phenomenon of the city’s architectural works in the Qajar era than other social groups.

Conclusion
In the present article, it was attempted to find out what the space structure of Hamadan had in the Qajar period by relying on the written sources and existing architectural works. With what was done, it turned out that the city was forming from three internal (city center), middle (urban areas and neighborhoods) and exterior (fence and suburbs). Hamadan Space Agency is also influenced by the pattern of Islamic cities of Iran, has a citadel (government, bureaucratic and administrative headquarters), Jame Mosque (Religious Center) and Market (Economic Heart) and other urban elements (schools, blessed shrines, intra city caravans, baths And ...) Somehow they were related to these three. Relying on written documents, it can be said that areas outside the city’s defense walls were exploited for agriculture and horticulture. During the Qajar period of Hamedan, with the center of the mosque and the bazaar in the south and southeast direction, it expanded and some new neighborhoods, along with urban elements such as mosques, baths, etc., are being constructed in this area. Most of the reasons for the expansion of the city’s texture in this area can be considered as the proper slope of the land and the lack of natural effects that could have been a barrier to construction. Due to the flow of the four rivers inside and outside the city during the Qajar period and their annual floods that occur as a result of heavy and long -term rainfall, as well as the slope of the city in the south -north, as a result of the flooding of the northern parts, as well as the natural complication. The so -called Mosalla hill in the eastern part, which prevented the development of the city’s physical structure, was the best way to develop it, southern and southeast side, along the rivers in the inner -city rivers of al -Wawsger and Davin. According to written and illustrated documents as well as existing architectural works and archaeological evidence, it can be said that the city of Hamedan in the Qajar period from the north to the Goulan Heights, Nazarbaig and Shalabafan, from the east to the neighborhoods of Imamzadeh Yahya and Zandis, from the West to the Bonehbazar and Sabadbafan neighborhoods were confined to the Kolapa, Doroudabad and Doguran neighborhoods from the south. Also, the result of studies on the role and influence of different social groups and classes in the formation of Qajar architectural works of Hamadan indicated that the traders and marketers of the marketers top the list of builders and sponsors of various buildings (religious, commercial, residential and public).

Abstract
Bulbous domes are among discontinuous double-shell domes and were built in Iran in the early nineth century A.H. Previous domes were shaped pointed and there was no bulge coming out beyond their base diameters. But in the Timurid period, dome profile was changed so that it began a return below the base of the arch, producing thereby a slight bulge. The main question is that what are the reasons for the changes in the appearance and structural elements between two shells after the initial formation of these domes in Central Asia and then their evolution in Iran. This research is written with the aim of finding the hidden aspects in the development of bulbous domes based on both historical documents, and architectural remains, and also examines the reasons of the changes created in these kinds of domes during four centuries in the context of cultural Iran. This study has a descriptive-analytical approach for exploring case studies, which are selected based on primary and secondary sources and also field research. The appearance changes of bulbous domes include removing flutes from the outer shell, adjusting the height of the drum and creating more bulge at the place where the outer shell joins the drum. In this article, the structural changes to improve the strength of the domes, the change in the number and proportions of the stiffeners to prevent the damage of the dome, as well as the shape and arrangement of the wooden struts to increase domes flexibility against seismic shocks, have been examined.
Keywords: Bulbous dome, narrow ribs, stiffeners, wooden struts, Timurid-Safavid architecture.

Introduction
Since the most obvious feature of Timurid architecture is its splendor, the architects of this period paid special attention to the dome than other architectural elements. In this era, domes were raised on high drums, and in order to achieve desired height on the exterior, architects usually built another shell on the top of the internal one. In such a way the dome profile is changed, so that it began a return below the base of the arch, producing thereby a slight bulge. Therefore, the bulbous dome is one of the innovations of the Central Asian architects during the Timurid period. The first cases of the bulbous domes in Central Asia have flutes on the outer shell; in addition, they have an oval-shaped structure. Construction of this domes continued with a few changes during the reign of Timur’s successors in Great Khorasan and within the current borders of Iran. To put it more clearly, after the Timurid period and during the rule of Safavids in Iran, construction of these domes continued with few changes. This study is dedicated to the analysis of the process of changes and also reasons for these changes in the appearance and structural elements of the bulbous domes according to the case studied in Central Asia and Iran during the Timurid and Safavid eras. The main question is, what changes have occurred in the appearance as well as structural elements, and as a result, the stability of these domes in the Timurid and Safavid periods in Central Asia and Iran, and what were the reasons for them.
Theoretical method of this research is based on the cultural history approach. Therefore, each case is viewed as a culture. Concerning this, three domes were selected from different regions of Central Asia (Turkestan, Samarkand, and Herat) and seven cases from Iran (Khorasan and Isfahan). Three main criteria for selecting the case studies can be listed: 1. Geographical and historical context; 2. Similarities of the cases during the Timurid period in Central Asia and the Safavid period in Iran, and; 3. Authenticity of the domes.  

Discussion
All the studied domes in Central Asia have a lofty cylindrical drum. The height of the drums was adjusted in Iran during the Timurid era, in Khorasan and also in the central regions of Iran. It is worth to mention that, construction of high drums in Central Asia, during the reign of Timur, and in Iran, during the reign of Shah Abbas I, can be seen as an expression of the visual effects of architecture as a manifestation of the power and reflection of the perfectionist personality of those Kings. 
The most important exterior characteristic of the studied domes is in the external shell (Avgon), where the drum and the external shell connected to each other. Therefore, in the bulbous domes, part of the weight load of the outer shell at the junction of the dome and drum is directed inward and less pressure is applied to the base of the monument.
Flutes move from their common place at the top of the external shell to the bottom, and transfer forces and lateral loads to the inside, and enhance the resistance of the dome against the thrust forces.
In Central Asia’s domes, we couldn’t find narrow ribs on the surface of internal shell. This is despite the fact that in most of the studied cases from the Safavid period, narrow ribs were used to transfer the weight of the stiffeners to the lower parts and base of the monument. It seems that, utilize of the narrow ribs in the Safavid domes was the invention of the Iranian elite architects to give cohesion to the double-shell domes, especially bulbous ones.
From the earliest bulbous domes, we can see stiffeners between two shells. These elements have different shapes. Establishing stiffeners, especially in the Avgon part, greatly reduce the destruction of the dome during earthquakes and shows the architects’ awareness of stiffener’s structural role and function.
The wooden struts are arranged somewhat circularly to help connect the stiffeners to increase flexibility against earthquake shocks.

Conclusion 
Changing process of bulbous domes in Iran includes removing the flutes from the external shell, adjusting the height of the drum and creating an avgon with more bulge at the junction of the external shell and drum. Domes with flutes in the Central Asia were a main characteristic of monuments. It seems that use of flutes, in addition to structural reasons, also had an aesthetic aspect; because, vertical and parallel concave and convex lines on the external shell make the domes look higher and add to the glory of the whole monument. Moreover, flutes help in transferring the thrust forces entered into the building and have a function like an avgon at the place of joining the dome’s drum. It seems that removing the flutes from domes in Iranian architecture of Timurid period should be considered as a result of the lack of a single political power in different regions of the country. Among other fundamental changes, we can notice domes with more bulge. During the Safavid period, architects learned and experienced the basic stages of bulbous domes and gained sufficient skill with regard to the morphological elements of dome and its strength. In this way, for aesthetic purposes, structural solutions such as creating narrow ribs on the internal shell of the dome and deepening the stiffeners in the avgon part have been used to maintain the integrity of the external shell. One of the reasons for the construction of narrow ribs is to transfer the compressive force of the stiffeners to the lower parts and bases of the dome and to strengthen their stability. In some cases, ribs were not used to connect stiffeners to the internal shell due to small diameter of the dome span. The changes made in the stiffeners from the Timurid period to the end of the Safavid period should be considered more related to their number, shape and proportions, which can be attributed not only to the creativity of local architects, but also to the architects’ complete awareness of the role and function of the stiffeners. These structural elements prevent the destruction of domes due to thrust forces (wind and earthquake). Wooden struts also make it possible to create a better connection between the stiffeners and external shell, as well as the connection between the components of the dome.

Abstract
Residential architecture as a living space for family members has been influenced by climatic and geographical conditions. Accordingly, some methods for designing climate-responsive architecture can be seen in historic houses of Iran, such as Ashtian. Therefore, this research aims to identify the influence of climate and geography on Qajarid residential architecture in Ashtian and to elucidate the strategies and measures employed by architects to mitigate negative effects and increase beneficial climatic and geographical influences. Questions are: What is the effect of climate and geographical features on the location and spatial distribution of Qajarid houses in the Ashtian? How did climatic and geographical factors affect the plan, form, and architectural features of Qajarid houses in Ashtian? Two hypotheses are: the topography of Ashtian, watercourses, and soil type have played a role in locating houses. Furthermore, the plan, form, and architectural features of the houses were influenced by climatic factors such as wind, angle and amount of sunlight, and temperature. ArcGIS, Google Earth, WRPLOT design software, AutoCAD, and SPSS software were used for data analysis. Based on the results, the architects were started the construction of the building by considering climatic factors such as sunlight angle, prevailing wind, temperature, and humidity. They have paid attention to the type and color of materials, size of windows and doors and courtyards, and size and location of rooms. Also, based on the models obtained from WRPLOT software, the dominant wind of the region in two directions east-west and west-east was identified and its effect on architecture was explained. The results of the analysis in SPSS also show the correlation between “type of land and social class of people”, “type of land and soil with reservoirs”, and “maximum wind speed and the number of floors”.
Keywords: Qajar Monuments, Climate-Responsive Architecture, Residential Architecture, Ashtian.

Introduction
Considering the geographical divisions of Iran, different architectural features have been formed in each geographical region (Memarian, 2012: 5). Although Qajarid architecture was influenced by modernism and non-Iranian patterns, climatic and environmental features have been among the most influential factors in Iranian architecture. It seems that architecture in Ashtian also has such characteristics. The development of the city of Ashtian during the Islamic era was due to its location in Iraq-e Ajam and the route of the pilgrimage to holy shrines of Iraq (Omidbeyki, 2015: 1). In the Qajar period, Ashtian was a place of residence for virtuous and pious people, writers, scholars, and politicians (Shirvani, 1897: 42), and various types of urban and suburban residential structures were built. 
This research aims to identify the influence of climate and geography on Qajarid residential architecture in Ashtian and to elucidate the strategies and measures employed by architects to mitigate undesirable effects and increase beneficial climatic and geographical influences. The study of these residential structures, with a focus on analyzing the role of geographical factors, provides insights into the interaction between the Qajar society and the specific climatic and environmental conditions of the region.
There are two main questions in this research: What is the effect of climate and geographical features on the location and spatial distribution of Qajarid houses in the Ashtian? How did climatic and geographical factors affect the plan, body, and architectural features of Qajarid houses in Ashtian? Based on these questions, the following hypotheses have been proposed: the topography of Ashtian, watercourses, and soil type have played a role in locating houses. Furthermore, the plan, form, and architectural features of the houses were influenced by climatic factors such as wind, angle and amount of sunlight, and temperature.

Discussion
In this study, eight Qajarid residential buildings in Ashtian County – as a cold and dry region in the Markazi Province - were studied, which are: the houses of Mirza Hedayatullah, Mirza Hasan, Nuraee and Mo’tamed al-Ayalah, as well as Mustofi Al-Mamalek (Agha) castle in Ashtian city, Abdulazim Gharib house in Garekan village and two feudal castles in Ja’farabad village (Figs 2-9). 
Based on the Google Earth photos, the Qajarid houses in Ashtian have been located in the middle of the southern slope of the mountain. Because the northern slopes of the mountains are in shadow and colder (Ghobadian, 2018, 101-102), While the southern slope is sunny and has better conditions for residence and other activities. Watercourses are usually threatened during floods and pose a threat to settlements (Negarsh, 2003: 137). The topographic analysis of the watercourses and hazardous slopes around the studied buildings indicates that less attention has been paid to the issue of watercourses in Ja’farabad, Garekan, and Ashtian. Furthermore, the city of Ashtian is located on QT2 soils, Ja’farabad on QT1 soils, and Garekan on MS and MQ soils (Figure 10). Based on this, the lands of Ashtian and Ja’farabad are relatively homogeneous in terms of resistance and provide relatively favorable conditions for construction. However, Garekan lands are weaker for building construction. In Addition, a very strong fault called “Talkhab” extends northwest to southeast, passes 12 kilometers southwest of Ashtian and 4 kilometers northeast of Ja’farabad (Fig 11). Historical reports also indicate destructive earthquakes in the years 855 AD, 958 AD, 1177 AD, 1316 AD, 1495 AD, and 1962 AD in this area (Ghodrati et al., 2010: 184). Therefore, the location selection of houses in the cities of Ashtian, Ja’farabad, and Garekan has been carried out without considering the earthquake hazard. 
The most prominent architectural features of cold and mountainous regions include small and confined urban and rural spaces, compact structures with interconnected buildings, narrow streets with limited width. Furthermore, Attention is given to solar orientation (Ghobadian, 2018: 99). The urban spaces in Ashtian are also small and confined, with a compact urban fabric (Figure 12), as well as Garekan and Ja’farabad. The main streets and thoroughfares are also narrow and have limited width. 
The study of the influence of the angle of solar radiation on the monuments of Ashtian for 11 AM at the beginning of each season showed that the difference in the angle of solar radiation between summer and winter in these regions is more than 35 degrees (Table 1). For this reason, a porch has been built in the north face of some houses, including Mo’tamed al-Ayalah, Nuraee, and Ja’farabad castles. The roof of these porches was like a canopy, and it protected the openings from the hot summer sun. But in winter, the slanting sunlight penetrated the into the interior spaces. Also, the orientation of the axis of the house plans in the east-west axis made the sunlight to be received more in the cold winter mornings in the southern facades.
In these buildings, the percentage of open space or courtyard area compared to the total building area is less than 35 percent. This is because in areas where the temperature is cold or very cold for most days of the year, most daily activities take place indoors. In the buildings of Ashtian, small openings were used to prevent heat exchange between the interior and exterior of the building. In the design of these openings, in addition to light, ventilation and the utilization of pleasant winds or prevention of unpleasant winds have also been taken into consideration. The output of modeling in WRPLOT software indicated that the prevailing wind in this city is predominantly east-west and west-east (Figure 13).

The outputs of the SPSS also showed the following
- A relationship between the type of land and the social class of the people living in the house: political people and officials have chosen areas with more suitable soil.
- A relationship between the type of land and soil with the presence of a water reservoir in the building: all Qajarid buildings in Ashtian city had water reservoirs. However the residents of Ja’farabad did not need a water reservoir. Because the underground water and the aqueducts were rich.

Conclusion
The study of Qajarid houses in the city of Ashtian has shown that some geographical and climatic factors have influenced the location, plan, structure, and architectural elements of these houses. However, architects have also overlooked some climatic and geographical variables in the location, design, and construction of these houses. In response to the first question, it should be noted that although these houses have been strategically and intelligently located in the southern foothills to easily capture sunlight and solar energy, they are all exposed to the risk of floods from the north and northeast along the watercourse. Nevertheless, the principles of urban space design and construction in mountainous and cold regions have been maximally observed in the city of Ashtian, and the analysis of the urban fabric and space in Ashtian indicates narrow streets and the integration of architectural units for better adaptation to the climate. Regarding the second question, this study has shown that the principles of design and construction of residential spaces, including plan, structure, architectural elements, and materials, have largely obeyed climatic and geographical factors such as the direction and intensity of sunlight, the prevailing wind direction, and the temperature in summer and winter. For example, the roofs of the buildings are flat, and the windows are small and proportionate to the direction of the sun and the prevailing winds of the region. The positioning of the windows facilitated the absorption of solar heat in winter and ventilation in summer. Small central courtyards and open spaces have been built in accordance with the climate of Ashtian. The number of floors in these houses corresponds to the intensity and speed of the wind, and the presence of architectural spaces with specific functions, such as water reservoirs, depends on the type of soil and the geographical characteristics of the region.

Abstract
Mausoleum buildings with ridged Dome, is one of the characteristics of religious architecture in the southern regions of Iran which was founded during the Ilkhanid to Safavid period. The main form of a ridged Dome is conical which the arrangement of its cubic components with different and varied shapes has a stepped mode. Studies that so far have been done on the structure of mausoleums with ridged Dome are more holistic. Therefore, the most important purpose of the present research is to explain and establish the architectural differences and similarities of four tombs which are located in different geographical areas in Southern Iran and belong to The Ilkhanid-Timurid era; and to study their susceptibility to various methods. The architecture of the mentioned historical periods under the title of Governmental (including the central sphere of governance of the Ilkhanid) and Local style (including special architectural and artistic features of the southern regions of Iran). The goal of the present research is to answer this question that what a meaningful form and decorative relationship is there between mausoleum buildings with non-governmental/indigenous ridged Dome and governmental structures? The result of the research clarifies that the architectural ornaments, which are used in the mausoleum of Mir Muhammad especially the high and deep vaults in the dome chamber and using the brick in the crown of its fluted Nar dome, represents the governmental style. The simplicity of the tomb form and usage of local material, building of conical Nar crown in the tombs of Baba Monir and Do-gonbadan and establishing symmetric ridged Dome in studied mausoleums is affected by local architecture of the mentioned regions. Also, it has been observed a kind of coexistence between local architecture and governmental style in some of the studied mausoleums. This research has been done with the approach of cultural history and descriptive-analytical method. The information has been gathered with the method of field investigation and library studies.
Keywords: Mausoleum Buildings, Ridged Dome, Ikhanid-Timurid Era, Architectural Style.

Introduction
The general shape of the ridged Dome is rock or conical; with the difference that its components, instead of a complete cone, has a scalariform (Zemorshidi, 2010: 349). This cover has been used in the late Seljuk era tomb buildings of Iran, especially in the south and southwest areas and its construction is significant throughout the Ilkhanid to Safavid eras (Sajjadi, 2017: 306). Most of the researchers believe that building of the ridged Dome follows specific geometric patterns. Its inner and outer cover represents that this structure comprises of several floors with similar geometric shapes and the geometric floors of the dome ascend rotationally from the Bashn of the dome chamber to its top. Moreover, meanwhile the floors of the dome go up, the dimensions of its ridged cubes become smaller and their height is reduced. Finally, they join together at the top of the dome (Zemorshidi,2017:350; Mashayekhi & Mahdavinejzad, 2012:297). Most of the conducted researches have a holistic framework and less attention has been paid to the structure of buildings with the ridged Dome and its changes in a certain period of time or a certain geographical area. The goal of the present research is to answer this question that what a meaningful form and decorative relationship is there between the non-governmental and governmental structures-at the intended political field-in the mausoleums with the ridged Dome. The importance of the present research and the necessity of doing it is also in identifying the tomb buildings with the ridged Dome that less researches have been done on it, and criticizing opinions which are provided by other researchers.

Materials and methods 
This research has been done with the approach of cultural history and descriptive-analytical method. The information has been gathered with the method of field investigation and library studies.

Data
Mausoleums of Do-gonbadan in Kookherd: The two mausoleums of Do-gonbadan are located in Hormozgan province, Bastak county and Kookherd village. Both mausoleums are burial places of two members of the Bani Abbasid family of Bastak (Bani Abbasian Bastaki,1960:57 & 58). The plan of both mausoleums is similar and consists of a simple square dome chamber. Also, both tombs have a ridged Dome with a star base. The decorations of Do-gonbadan tombs are associated with stucco, one of which is stalactite work in the interior view of the dome.

The mausoleum of Mir Muhammad 
The mausoleum of Mir Muhammad Hanafi is built on Kharg island of Bushehr county. Based on the tomb inscriptions, the building is attributed to Mir Muhammad Hanafi and was built during the Ilkhanid period. This tomb consists of a cruciform shrine and a square mausoleum which is adjoined to the south side of the dome chamber. A ridged Dome is constructed on top of the shrine that has a star base. The decorations of the tomb include mosaic-faience tilework and lustre tiles of dado which have animal, geometric and vegetal motifs on their surface, Also, the interior surface of the dome is decorated with chalky muqarnas.

The mausoleum of Baba Monir
The mausoleum of Baba Monir is located in Fars province, Noorabad Mamasani county and in a village called Baba Monir. The plan of the tomb is square. Its interior view includes a central dome chamber and a vaulted corridor that surrounds the dome chamber. Deep piers have given a cruciform design to the dome chamber. The dome of the tomb is ridged and has a star base. Chalky muqarnas is used in the interior surface of the dome.

Discussion
The conducted researches indicate that all the studied mausoleums belong to religious personages. Also, all of them have been built on the commercial path or near the commercial path. Moreover, there are similarities and differences in the features of studied tombs; The most important similarities between studied tombs are the usage of cruciform plan in the dome chamber of Baba Monir and Mir Muhammad mausoleums, the usage of the ridged Dome with the star base on top of dome chambers of all mausoleums, and the application of chalky muqarnas in the interior view of the dome of these tombs. The differences include using the simple square plan in the mausoleums of Do-gonbadan in Kookherd, and existence of the fluted Nar crown on top of the Mir Muhammad dome while there is a simple conical crown on top of the Baba Monir and Do-gonbadan dome. Besides, the only tilework decoration is in the Mir Muhammad tomb. In sum, the architectural features represent that Mir Muhammad tomb is more affected by the architecture of the governmental style. Because, it was built on the main trade route. But, the architectural features of Baba Monir and particularly Do-gonbadan are more non-governmental/local. Because these tombs were built on the side trade roads. Therefore, architects of these two tombs have not had much chance to become familiar with other architectural methods.

Conclusion
Studied mausoleums are the burial place of important religious personages and are built single, in an open space. These tombs were located on the trade routes. The location of Mir Muhammad tomb in Kharg island and on the transregional trade route of Islamic lands with East Asia has increased its importance. The architectural decorations of Mir Muhammad mausoleum have more variety in comparison with other mausoleums and it reveals the influence of various architectural styles, especially the Ilkhanid-Timurid architectural style. This effectiveness has been observed to a small extent in Baba Monir tomb compared with Mir Muhammad tomb. Whereas, mausoleums of Do-gonbadan in Kookherd have the least influence from the governmental buildings of the Ilkhanid-Timurid era. However, the method of constructing the ridged dome in all mausoleums has been executed skillfully in terms of structural and geometric form. In general, the constructing of the ridged symmetric domes in each four tombs signifies the powerful influence of the local architectural style in their structure. However, the influence of other architectural styles in these mausoleums is not the same. There is a kind of coexistence between the local and governmental architectural styles in the tomb of Mir Muhammad in Kharg. The influence of the local architecture is more obvious in the mausoleums of Baba Monir and particularly Do-gonbadan.