The oracular sites had a high value in Ancient Greece. They were the connection between the mortal and the immortal worlds. Every oracular site was the spokesman of a different God who expressed him or herself through the priestesses of Pythia. Villagers, kings, warriors, constructors and politicians came from distant places to listen to the prophecy of the Gods. The words they were told were the will of the Gods and determined their fate and behavior. In order to enter the temple, people had to bring many offerings for the Gods, which were offered during open air ceremonies where people had to wear white clothes as a sign of purity.

The most known oracular sites of the Ancient Greece are the Oracle of Zeus in Dodona and the oracle of Apollo in Delphi. .

• In Dodona, the priests told the will of Zeus under the effects of the leafs of a holy oak or of the tones of the holy pigeons that sat on this tree.
• In Delphi, there was an opening in the floor that inspired those who sat next to it and a holy spring surrounded by holy laurel. There, a priestess sat on a tripod and, high from the water vapor, received the will of the Gods.

The oracles were consulted in all situations and their answers determined the conduct of mortals in front of war, revenge and the understanding of life. All the stories about heroes and their myths are strongly related with the oracle or its sayings. These sayings were usually enigmas difficult to interpret and many times with a double interpretation that, in a way, protected the oracles from incorrect decisions. Apart from the priests, there were also some seers who had a special relation with the Gods and to whom many people went to discover their fate. The most famous were Teiresias and Kalchas.

There were not many who would dare to go to a war without a positive answer from the oracle. So many people were arriving to Delphi from places as far as the North of Africa to listen to the will of the Gods, that it possessed an incredible wealth. However, all this wealth was stolen by the Romans after the disintegration of the Hellenic Kingdom.

Of course, there was always the danger of an oracle bribery. With the sayings of the oracle it was easy to get the support of the national assembly and even from a great part of the citizen. For this reason, it is not crazy to think that the oracle was serving to the political power up to a certain extent.