The Shrine of the Millennium Stone (also known as the Shrine of the Underworld) is the location of the Millennium Stone, where the Millennium Items originated. If all seven Millennium Items are placed into the stone, a door to the afterlife is opened. Thief King Bakura used the stone in his Shadow Game with Pharaoh Atem to summon Zorc Necrophades. In the present day, Yugi had placed the items in the stone before his final Duel with Atem so that the Eye of Wdjat could separate their spirits into two physical bodies so that the Ceremonial Battle could begin.
In The Dark Side of Dimensions movie (taking place six months later), archaeologists excavated the ruins under the orders of Seto Kaiba, where pieces of the Millennium Puzzle were recovered. After the excavation, Mani found and recovered the Millennium Ring.