As portals to the supernatural realm that creates and animates the universe, caves have always been held sacred by the peoples of Mesoamerica. From ancient times to the present, Mesoamericans have made pilgrimages to caves for ceremonies ranging from rituals of passage to petitions for rain and a plentiful harvest. So important were caves to the pre-Hispanic peoples that they are mentioned in Maya hieroglyphic writing and portrayed in the Central Mexican and Oaxacan pictorial codices. Many ancient settlements were located in proximity to caves. This volume gathers papers from twenty prominent Mesoamerican archaeologists, linguists, and ethnographers to present a state-of-the-art survey of ritual cave use in Mesoamerica from Pre-Columbian times to the present. Organized geographically, the book examines cave use in Central Mexico, Oaxaca, and the Maya region. Some reports present detailed site studies, while others offer new theoretical understandings of cave rituals. As a whole, the collection validates cave study as the cutting edge of scientific investigation of indigenous ritual and belief. It confirms that the indigenous religious system of Mesoamerica was and still is much more terrestrially focused that has been generally appreciated.