Marco Polo describes how fire worship came to Persia.
THE TRAVELS OF MARCO POLO
CHAPTER XI : OF THE PROVINCE OF PERSIA.
"...After three days journey you come to a castle which is called Palasata, which means the castle of the fire- worshippers ; and it is true that the inhabitants of that castle worship fire, and this is given as the reason. The men of that castle say, that anciently three kings of that country went to adore a certain king who was newly born, and carried with them three offerings, namely, gold, frankincense, and myrrh: gold, that they might know if he were an earthly king; frankincense, that they might know if he were God; and myrrh, that they might know if he were a mortal man. When these magi were presented to Christ, the youngest of the three adored him first, and it appeared to him that Christ was of his stature and age. The middle one came next, and then the eldest, and to each he seemed to be of their own stature and age. Having compared their observations together, they agreed to go all to worship at once, and then he appeared to them all of his true age. When they went away, the infant gave them a closed box, which they carried with them for several days, and then becoming curious to see what he had given them, they opened the box and found in it a stone, which was intended for a sign that they should remain as firm as a stone in the faith they had received from him. When, however, they saw the stone, they marvelled, and thinking themselves deluded, they threw the stone into a certain pit, and instantly fire burst forth in the pit. When they saw this, they repented bitterly of what they had done, and taking some of the fire with them they carried it home.
"And having placed it in one of their churches, they keep it continually burning, and adore that fire as a god, and make all their sacrifices with it; and if it happen to be extinguished, they go for more to the original fire in the pit where they threw the stone, which is never extinguished, and they take of none other fire. And therefore the people of that country worship fire. Marco was told all this by the people of the country; and it is true that one of those kings was of Saba, and the second was of Dyava, and the third was of the castle. "