A mysterious underground place of prayer dating back to age of Parthian empire, placed 12 km far from Maragheh observatory. This temple is known as the oldest Mithraism temple in Iran. Mithraism is a faith emerged before Zoroastrian in Persia. Mithra was a deity of sun that people worshiped her from India to Europe.
In Mithraism its believed that Mithra was an angle born in a cave, so they used to worship Mehr in any cave they thought there is probably the birthplace of Mehr. Mithraism faith considered four elements of nature (water, air, soil and fire) as sacred elements.
The structure of this temple is consisted of dome, altars, a main hall and two chambers. This temple was not only for praying Mehr, but also it was a place used for praying different religions during the time, for example, during the Ilkhanid era, it was used as a convent by Sufis. During Safavid era, turned to pilgrimage place, also Mullah Masoum Maraghi is buried there. This temple is a cemetery of ancient structure. The underground structure offers great sense of silence