Delphi, with a population of 1,500, is one of the most beautiful and impressing landscapes of Greece, and the centre -"Omphalos "- of the world, according to the ancient myth. It was already inhabited in the prehistoric times and later -especially during the classic times- obtained great historic importance, as it has been linked with the most significant events of Greek history. Apollo, the God of catharsis and the genuine oracle, dominated earlier forms of worship in the Delphi. He taught people the "metron", that is prudence and modesty, which became the most ethical and peaceful expression of the Greek spirit.