The temple is an even later development: from Herodotus it is known that in the mid-5th century BCE the Zoroastrians worshipped to the open sky, ascending mounds to light their fires.
[8] Strabo confirms this, noting that in the 6th century, the sanctuary at Zela in Cappadocia was an artificial mound, walled in, but open to the sky, although there is no evidence whatsoever that the Zela-sanctuary was Zoroastrian.
Following the rise of the Sassanid dynasty, the shrines to the Yazatas continued to exist, but with the statues – by law – either abandoned or replaced by fire altars.
While the fires themselves had special names, the structures did not, and it has been suggested that "the prosaic nature of the middle Persian names (kadag, man, and xanag are all words for an ordinary house) perhaps reflect a desire on the part of those who fostered the temple-cult ... to keep it as close as possible in character to the age-old cult of the hearth-fire, and to discourage elaboration".
[citation needed] The oldest remains of what has been identified as a fire temple are those on Mount Khajeh, near Lake Hamun in Sistan.
Archaeological remains and literary evidence from Zend commentaries on the Avesta suggest that the sanctuary was surrounded by a passageway on all four sides.
"On a number of sites the gombad, made usually of rubble masonry with courses of stone, is all that survives, and so such ruins are popularly called in Fars čahār-tāq or 'four arches'.
"[16] Ruins of temples of the Sassanid era have been found in various parts of the former empire, mostly in the southwest (Fars, Kerman and Elam), but the biggest are those of Adur Gushnasp in Media Minor (see also The Great Fires, below).
[17] Apart from relatively minor fire temples, three were said to derive directly from Ahura Mazda, thus making them the most important in Zoroastrian tradition.
The Bundahishn, an encyclopaedic collection of Zoroastrian cosmogony and cosmology written in Book Pahlavi,[18] which was finished in the 11th or 12th century CE, states that the Great Fires had existed since creation and had been brought forth on the back of the ox Srishok to propagate the faith, dispel doubt, and protect all humankind.
These divisions are archaeologically and sociologically revealing, because they make clear that, since from at least the 1st century BCE onwards, society was divided into four, not three, feudal estates.
In the early 20th century, A. V. Jackson identified the remains at Takht-i-Suleiman, midway between Urumieh and Hamadan, as the temple of Adur Gushnasp.
The location of the Mithra fire, i.e. that of Burzen-Mihr, Jackson "identified with reasonable certainty" as being near the village of Mihr half-way between Miandasht and Sabzevar on the Khorasan road to Nishapur.
However, according to the Greater Bundahishn, it was moved "upon the shining mountain of Kavarvand in the Kar district" (the rest of the passage is identical to the Indian edition).
[20] If this identification is correct, the temple of the Farnbag fire then lay 10 miles southwest of Juwun, midway between Jahrom and Lar.
Under threat of war (probably in 1465), the fire was moved to the Bahrot Caves 20 km south of Sanjan, where it stayed for 12 years.
Sassanid coins of the 3rd-4th century CE likewise reveal a fire in a vase-like container identical in design to the present-day afrinagans.
It has been proposed that the term is a throwback to the age of the shrine cults, the name being retained because all major Zoroastrian rituals were solemnized between sunrise and noon, the time of day especially under Mithra's protection.
This is largely due to the financial support of such places by one Arbab Rustam Guiv, who preferred the dialectal Iranian form.
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.
A list of the nine Atash Behrams: The outer façade of a Zoroastrian fire temple is almost always intentionally nondescript and free of embellishment.
Connected to this anteroom, or enclosed within it, but not visible from the hall, is the innermost sanctum (in Zoroastrian terminology, the atashgah, literally 'place of the fire'[2] in which the actual fire-altar stands).
Only priests attached to a fire temple may enter the innermost sanctum itself, which is closed on at least one side and has a double domed roof.
In Indian-Zoroastrian (not evident in the modern buildings in Iran) tradition the temples are often designed such that direct sunlight does not enter the sanctuary.
In one corner hangs a bell, which is rung five times a day at the boi – literally, '[good] scent'[24] – ceremony, which marks the beginning of each gah, or 'watch'.
There was a custom in India that Zoroastrian women were not allowed to enter the Fire Temple and the Tower of Silence if they married a non-Zoroastrian person.
The priest will use a special ladle to proffer the holy ash to the layperson, who in turn daubs it on his or her forehead and eyelids, and may take some home for use after a Kushti ceremony.