Since the Mycenaean period, Delphi was at the same time a small city and a religious center. In the beginning it was its urban character what dominated, with walls, remains of houses and necropolis. Very few remains suggest that at that time there was a superior cultural activity in comparison with other cities, and yet, there are reasons to think that immediately under the walls and next to a fountain -the Casotide- there could have been already a fortune teller living there. Later, after some centuries from which we know very little, a sanctuary for Apollo was installed there and appropriated the oracle that became an essential part of the cult. Since then, the population lost relevance due to the religious nature of the place: without doubt it provided the priests and the fortune teller -the Delphi Pythia-, but the sanctuary obtained a pan-hellenic character, opened to all Greeks, and dominated the region restricting the development of a real independent polis next to it. Thus what is needed is to study the sanctuary, walk through it, visit its main monuments, and above all, get closer this curious phenomenon of divine possession that made the woman emitting the oracles go into ecstasy.