Abstarct: The connection between mysticism and architecture is so profound and extensive that imagining the separation of architecture from mysticism seems impossible. This interdependence exists across divine religions and the indigenous arts of all nations, but it is more evident in Iran. Therefore, it can be said that mysticism belongs to the very essence and nature of all religions, and religion has no more effective tool or superior interpreter than art—particularly architecture—for introducing and manifesting itself. Likewise, architecture has had no better supporter than religion. According to the beliefs of ancient Iranians, mountains arise from the union of heavenly forces with the earth. For this reason, mountains have held symbolic significance in the history of Iranian architecture and play a fundamental role in the continuity of life and fertility. This aspect of nature first manifests itself in the earliest temples or ziggurats, whose form and concept symbolize the mountain and were built to convey divine truth from the spiritual realm to the material world. During the Parthian era, domed structures with four arches (known as chahar-taqi or dome chambers) entered Iranian architecture. In the third century after the rise of Islam, the dome chamber—as a symbol of Sasanian rule—was incorporated into Islamic mosques. In the Seljuk period, the transitional zone between the square plan and the circular dome in dome chambers became two-tiered: the square first transitions to an octagon, and then in the upper level to a hexadecagon (16-sided form). This structural achievement has astonished art lovers and architects worldwide, for behind the physical form of the dome chamber lies a profound meaning that creates an unbreakable bond between geometry, color, and ornamentation (the science of the manifestation of existence) and philosophy (the science of existence itself). Muslim architects, like other Islamic artists, employed symbols to express the deeper meanings embodied in the form of the dome chamber. Symbolism is a concept from which the Muslim architect cannot escape in creating his works. Undoubtedly, baxsed on his understanding of the universe and his own place within the cosmic order, the Muslim architect was able to discover the mysteries of existence as truths manifested in the created world and, in a further step, to embody those meanings in the realm of human legislation and creation. Decoding symbols, grasping the meaning of the cosmic order, and manifesting that meaning in symbolic artistic form—this is the essence of the Muslim architect’s art. The dome chambers of mosques and mausoleums guide the soul upward, evoking transcendence and reminding one of the structure of the universe. In the theoretical mysticism of Ibn Arabi and the commentators of his school, existence is divided into levels known as the Five Divine Presences (Hadrat al-Khams). These levels are: the Absolute Unseen (al-Ghayb al-Mutlaq), the Absolute Manifest (al-Shahadah al-Mutlaq), the intermediary realms of manifestation (the Unseen close to the Absolute Unseen and the Unseen close to the Absolute Manifest), and the Perfect Human (al-Insan al-Kamil, the comprehensive being). The physical structure of the dome chamber—consisting of the dome apex, the dome itself, and the cubic baxse—emerges from the architect’s imagination and displays a process of multiplication that evokes the levels of existence in the descending arc. The geometry, colors, and ornaments of the dome chamber serve as symbolic exxpressions of these meanings (the levels of existence). If we regard the dome chamber as a microcosm of the universe, its interior space corresponds to the levels of existence in the descending arc: • The apex of the dome symbolizes the realm of the Absolute Unseen (Unity, Wahidiyyah), represented symbolically in color by white. • The dome itself (the vault or heaven) symbolizes the Unseen close to the Absolute Unseen (the realm of Jabarut, divine power), represented by the color yellow. • The transitional zone of the dome, typically octagonal, symbolizes the Unseen close to the Absolute Manifest (the realm of Malakut, the angelic realm), most often represented by blue or green. • The horizontal section of the dome chamber, rising as a cubic form, symbolizes the Absolute Manifest (the realm of Mulk, the physical world), expressed through combinations of green, white, and red.