Anatolia offers both the best and the worst kind of evidence for religious history, sometimes within a few hundred miles of each other.
The best is Hattusa. Excavation of the Hittite capital recovered thousands of clay tablets from palace and temple archives, and once Bedrich Hrozny showed in 1915 that Hittite was an Indo-European language they became readable. They contain festival calendars, treaty oaths sworn before named deities, prayers of specific kings in specific crises, and the rituals of individual practitioners recorded under their own names. The Hittite state absorbed the gods of the peoples it ruled and spoke of the thousand gods of Hatti, so the archive documents a deliberately plural religion from the inside.
The worst is Gobekli Tepe. Its enclosures of carved pillars were raised before pottery and before writing, and there is no text and no possibility of one. Everything said about what the site was for is inference from architecture and imagery, and the confident accounts in popular circulation are not supported by anything the excavation can establish.
Between them the region carries most of the religious registers found elsewhere in this collection: Phrygian worship of the mother goddess who reached Rome as Cybele, Greek cities with their own cults, and the early Christian communities addressed by the first letters and the councils, Nicaea and Chalcedon among them, at which Christian doctrine was defined.