The Roman mundus was located in the Comitium, on the Palatine Hill. This stone was ceremonially opened three times a year, during which spirits of the blessed dead (the Manes) were able to commune with the living. The three days upon which the mundus was opened were August 24, October 5, and November 8. Read more
A lapis manalis (Latin: "stone of the Manes") was either of two sacred stones used in the Roman religion. One covered a gate to Hades, abode of the dead; Festus called it ostium Orci, "the gate of Orcus". The other was used to make rain; this one may have no direct relationship with the Manes, but is instead derived from the verb manare, "to flow". Read more