Fire, the provider of heat and light and the source of life and growth, was the center of all religious rituals of the ancient Indo-Iranians which plays an important role in the religious ceremonies of the Zoroastrians. A remnant of the Atashkooh fire temple is located close to town of Nimvar, Markazi Province, central Iran. The temple dates back to Sassanid Period (224- 651 AD) which was built originally as a square four arch shape, comprising stony columns for supporting its semi-sphere shape dome. Inside the temple there were some chambers and also a porch to locate the holy fire. The temple was intact up to about 900 A.D.