A fire temple in Zoroastrianism is the place of worship for Zoroastrians, often called dar-e mehr (Persian) or agiyari (Gujarati). In the Zoroastrian religion, fire together with clean water are agents of ritual purity.
Functionally, the fire temples are built to serve the fire within them, and the fire temples are classified (and named) according to the grade of fire housed within them. There are three grades of fires, the Atash Dadgah, Atash Adaran, and Atash Behram.
I . The Atash Dadgah is the lowest grade of sacred fire, and can be consecrated within the course of a few hours by two priests, who alternatingly recite the 72 verses of the Yasna liturgy.
II . The next highest grade of fire is the Atash Adaran, the “Fire of fires”. It requires a gathering of hearth fire from representatives of the four professional groups (that reflect feudal estates): from a hearth fire of the (1) priesthood (2) the soldiers and civil servants (3) the farmers and herdsmen and (4) artisans and laborers. Eight priests are required to consecrate an Adaran fire and the procedure takes between two and three weeks.
III . The highest grade of fire is the Atash Behram, “Fire of victory”, and its establishment and consecration is the most elaborate of the three. It involves the gathering of 16 different “kinds of fire”, that is, fires gathered from 16 different sources, including lightning, fire from a cremation pyre, fire from trades where a furnace is operated, and fires from the hearths as is also the case for the Atash Adaran. Each of the 16 fires is then subject to a purification ritual before it joins the others. 32 priests are required for the consecration ceremony, which can take up to a year to complete.
Where is Udvada ?
Udvada is a town in Gujarat, renowned for its Zoroastrian Atash Behram. This place of worship is the oldest still-functioning example of its kind, and has established Udvada as a pilgrimage center for Zoroastrians the world over.