Reinterpretation of form and function in the Apadana Palace based on ancient Indo-Iranian sources

One of the most important and magnificent palaces in the Achaemenid citadels of Susa and Persepolis is the palace known as Apadana. Apadana palace in Susa is called by this name because of having an inscription naming this palace Apadana on the remaining pillars, and a palace with a similar physical structure in Takhte Jamshid despite not having an inscription with a name is called by this name because of this similarity. Numerous archaeological, historical, architectural and urban planning researches have been conducted on Achaemenid cities and citadels for a long time, and the function of these palaces, especially the palaces and buildings of Persepolis, has always been a matter of debate for experts. However, previous researches in order to understand the meaning of Apadana and the physical structure of this building and its function have focused less on the historical and racial history of the Persian tribe, which we know is a branch of Indo-Iranian tribes. This research with the help of allegorical mythology method of Georg Friedrich Creuzer which is a method focused on finding the meaning behind the form of an artwork by the help of finding narratives and myths behind it seeks to find an new interpretation for the function behind the form of Apadana palace. Thus, this historical study in the rich ancient Indo-Iranian texts showed that based on Indo-Iranian etymology the word Apadana means a holy and glorious place of gathering and presence, and over the years it has been used in the meaning of palace with columns, public palace and outer palace. Also, the study of the physical form and plan of the building showed that the plan of the building as well as many details used in it was based on the Vastu Purusha Mandala diagram in the Vastu Shastra, which is the knowledge of building the physical environment, the traditional knowledge of architecture and urban planning, in Indo Iranian culture. Based on the mythological narrative of the formation of this mandala, the Purusha, the cosmic man has been fixed on the earth by the gods, and with the presence of these celestial and solar gods, the image of the sky is reflected in this plan, and this is the scene on which the movement of the sun and the moon and their years drawn and calculated, And also on this plan the constant cycle of days and time is measured. So this palace is an image of the sky and the daily and annual movement of the sun and the moon is reflected on it, and in this way it is the best place to celebrate important annual events such as Nowruz, Mehrgan, Tirgan, etc.