Geometry in the Dome of Sheikh-Zahed-e-Guilani Shrine: A Model for Designing Domes in the Southern Coasts of the Caspian Sea

This research is an attempt to discover the logic behind the specific architectural design of Sheikh Zahed-e-Guilani Shrine, a monument dating back to late Timurids and early Safavids in Lahijan in Northern Iran. The hypothesis behind this research is that the design of this dome must be based on some exact geometrical relations and proportions which have not been discovered yet. After mentioning the architectural merits of the building to be studied, the important role of geometry in architectural design in old days is discussed, both in Islamic and non-Islamic architecture. This brief discussion justifies the use of geometrical analysis in order to discover the logic behind the form of this monument, specially its unique pyramidal dome. The research continues to use a geometrical analysis to understand the specific form of the dome in the main façade of the building. It illustrates the process of designing the specific pyramidal dome of the building step by step; the process that the real designer of the building had probably gone through more than five centuries ago when designing this monument. Analysis shows that a network of 45 degree slanting lines has been used as the geometrical base of the form of the dome and the whole façade; a network which is not seen in the design of traditional architectural works in central Iran and can be considered a local approach to the use of geometry in architectural design. Concerning the importance of the findings of this research two points are discussed: first, discovering these hidden geometrical relations is again a reminder of the prominent role of geometry in old architectures which is in turn an indication about how one should "read" traditional architectural works. Second, the geometrical system, used in designing this dome, can be utilized in a creative way to design new domes for religious buildings to be built in the specific cultural and geographical context of the southern coasts of Caspian Sea. The article discusses two current popular attitudes towards designing new domes in this region: the more widespread one is purchasing and installing a prefabricated metal dome with a curved profile on the roof of buildings; A profile which belongs strongly to the central parts of Iran. These domes are not usually well-integrated into vernacular architecture and the result usually suffers a sense of doubled-identity. In the second attitude, the traditional pyramidal domes of the region are imitated without enough creativity. They try to reconstruct the exact traditional forms using new building technology. Although this method considers the architectural culture of its context and tries to be respectful to it, again the non-creative result is not satisfactory. Using a form giving geometrical system similar to the one used in designing the dome of Sheikh Zahed Shrine, today's creative designer can design new domes which are new and creative in their formal design and at the same time are traditional and have their roots deep in vernacular architecture.