The ancient people of the Mediterranean had such faith in the Oracle’s visions that no major decision was made without consulting her first. Greek and foreign dignitaries, heads of state, and common folk made the pilgrimage to the Delphi sanctuary, and paid great sums for Pythia's oracles. Since the sanctuary only served the public a few days over nine months out of the year, great amounts of money were paid by the richer ones in order to bypass the long line of pilgrims.Her prophesies were considered to come from Apollo. However, there is another theory. Archeologists who have invested the temple ruins found a geologic chasm that emits gases, which was probably the real way “The Oracle” entered a trance-like state and had visions. The gas is speculated to be naturally occurring ethylene.
For some reason, this reminds me of the sixties where people would use drugs to enhance their creative ability. I also don't think these women could have lived very long.