Let's compare again: Greek World featured: Spoiler : Judaism Christianity Zoroastrianism Hinduism Mesopotamian Polytheism Greek Polytheism Egyptian Polytheism The Ancient Mediterranean features: Spoiler : Judaism Christianity Zoroastrism Animism Mesopotamian Gods Olympian Gods Heliopolitan Gods This is my list instead: Spoiler : Judaism Christianity Zoroastrianism Triplism (Celtic Polytheism) Mesopotamian Polytheism Olympian Polytheism (Greek) Heliopolitan Polytheism (Egyptian) Greek World, IIRC, dropped cathedrals, monasteries and shrines. Religion wasn't that important in classical age, and there's some lack of buildings. There were only church, synagogue, fire temple, mandir, ziggurat, temple, obelisk. Maybe now we could have more material to work on. What do you think?