Re: The most ancient would be Judaism
You're right about the Olympics. They don't really count because they weren't continuous. Judaism does fit the mark, though. And what's really remarkable is that they did it without any geographical anchor, like the Church of Rome. It is also remarkable that after the diaspora large segments of Judaism were not only geographically isolated from a homeland, but from one another, and they had no unifying leadership hierarchy. They are indeed a very special people, I am in awe of their accomplishments.