The Oracle
Near Ioannina is the most important oracle of Zeus and the one the Greeks believed to be the oldest is the oracle of Dodona. Dodona is a city in northwestern Greece, near an important pass travelers used to get around Mount Tomaros. It seems that the spot was originally used to worship the personified earth deity Gaia (here known as Dione), and later assimilated into the cult of Zeus.
According to mythology, the black dove from Thebes landed in an oak tree at this spot and stated with a human voice that a sanctuary of Zeus must be founded here. So it was. The tree was later encircled with bronze cauldrons that touched the sides of one another so that they constantly rang or buzzed, providing a layer of magical protection that guarded the tree against evil.
The Greeks believed that Zeus had chosen this oak tree in Dodona as his oracle, which meant you could ask Zeus a question and expect a yes-or-no response. Basically, a pilgrim would trek to the site and write their question on a tablet. Zeus answered through the rustling of leaves or doves. Priests or priestesses of the site interpreted the rustling and told the pilgrims if Zeus had answered yes or no. It seems that the oracle of Dodona was almost entirely used to ask private and personal questions, as opposed to the famous oracle at Delphi which was used for matters of government and politics.
