Often referred to as the Zoroastrian Fire Temple, this elegant neoclassical building, reflected in an oval pool in the garden courtyard, houses a flame that is said to have been burning since about AD 470. Visible through a window from the entrance hall, the flame was transferred to Ardakan in 1174, to Yazd in 1474 and to its present site in 1940. It is cherished (not worshipped) by the followers of the Zoroastrian faith – the oldest of the world's monotheistic religions.

With wings outstretched to represent good thoughts, good words and good deeds, the Fravahar symbol graces the entrance of the building. The downward-pointing tail feathers symbolise bad thoughts, words and deeds while the large ring suggests the dualism of good and evil. The bearded man, representative of aged wisdom, holds a smaller ring signifying loyalty.

The museum houses a few relics and, of more interest, a set of informative panels explaining some of the principles and customs of the Zoroastrian religion, which dates back some 5000 years. There are about 4000 Zoroastrians living in Yazd, one of the largest such concentrations in Iran.