Favorite is hard to say. But I visited the ancient sanctuary of Delphi in Greece recently which I found very powerful. It was already a place for prophecies and worship long before Ancient Greece was at its height.
Discussion
Wow!! It’s incredible! What kind of prophecies? 😲
The big Oracle of Delphi, priestesses inhaling the fumes from a deep crack in the Earth and mumbling prophecies from the God of Light Apollon himself :) ... of worldy affairs of kings and emperors, of personal matters or of spiritual nature.