¶ … verdant hills of Delphi were a perfect place to perform rituals and ceremonies in honor of the gods. Olive groves, cypress trees, flowing waters, and distant mountains added to the magnificent aura of that sacred ground. While the origins of Apollonian festivals at Delphi are obscured by time, it is certain that Apollo was the presiding deity at this ancient site. By the eighth century BC, Apollo reigned over the hills of Mount Parnassus; his cult was in full force. Homer mentioned Apollo in his Iliad, and the myths surrounding him are plentiful. Apollo was honored in his many aspects as Delphi through religious rites and festivals, as well as through the Oracle of Delphi, who channeled the god's wisdom in order to advise peasants and politicians alike. Apollo was the presiding god over Delphi three seasons of the year, and only in the winter did Dionysian rites replace those of the sun god. Apollo was worshipped in Delphi as the god of music, poetry, and the sun. His festivals included the Septeria, held once every eight or nine years, and the Pythian Festival, held every four years. These festivals served as much of a political and cultural purpose as a religious and mythological one. Apollo was honored at Delphi through these festivals, the Oracle, and the name of the site itself. Apollo, the mighty son of Zeus and Leto, slaughtered the Python, a dragon-snake that guarded Delphi. His brave and murderous act...

However, his return to Delphi after his exile was marked by revelry and celebrated once every eight or nine years as the Septeria, or "feast of purification." This festival, usually celebrated with a holy drama or play, commemorated Apollo's killing of the Python as well as his nine-year purification exile. The drama was probably enacted on the Halos, a rock-paved area otherwise used as a threshing floor for grain. The Halos is located on the site of Delphi, along the Sacred Way leading to the main sanctuary. Within that main sanctuary sat the Oracle of Delphi, known also as the Pythia.
The Python lends its name not only to the well-known snake but also to the Oracle of Delphi herself. The Pythia was called such because of her connection with the Python and to Apollo, its killer. Furthermore, Delphi was named after the god. Apollo's cult title was "Delphinos," meaning dolphin. Myths of his transforming himself into a dolphin gave him this title, and the Greeks paid Apollo respect by naming a sacred site after him.

The shrine of Apollo at Delphi was considered to be the center of the earth. Zeus asked two eagles to fly in opposite directions, and wherever they met would be the earth's center. They joined at Delphi shrine to Apollo, hence called the Omphalos, or the…