This book takes the reader on a fantastic journey through a wide range of cultures and traditions to examine the phenomenon of ecstatic visionary experiences from Sumerian Gilgamesh and the Taoist Immortals to the imaginative fiction of Jorge Luis Borges. The author provides a comprehensive tour of otherworldly journeys common from immemorial times among shamans, magicians, and witches, and illustrates their connection with such modern phenomena as altered states of consciousness, out-of-body experiences, and near-death experiences.