The infusion of an Indo-European (Iranic) language, culture, and genetic element into the Kurdish population over the two millennia preceding the Christian era also entailed the incorporation of Aryan religious practices and deities into indigenous Kurdish faith(s). Zoroastrianism, Judaism, Manichaeism, and Christianity successively made inroads into Kurdistan. The most holy of Zoroastrianism's three grand fire temples, that of Âzargushasp, was built at the holy site of Ganzak (modern Takâb) in eastern Kurdistan in the northern environs of the Kurdish city of Bijâr. The irnposing ruins of the temple are still extant. Despite this, Zoroastrianism did not succeed in converting any appreciable proportion of the Kurds. In fact, it was the indigenous Kurdish religions that, in addition to deeply influencing Zoroastrianism, on two instances attempted to absorb that religion.