The Sanctuary of Demeter at Eleusis, 18km from Athens, was the epicentre of the panhellenic religious cult known as the Eleusinian Mysteries. Twice a year initiates proceeded from the Acropolis to the sanctuary via the Hiera Hodos. It is highly likely that ergot, a psychotropic fungus that grows of certain cereals, was ingested during the initiation. The Cult of Eleusis was already an ancient religion by the time Athens reached its cultural zenith in the 5th century BC. It survived into the Roman era when the rise of Christianity prevailed.