Rennes-le-Château

From Xenosaga Wiki

Rennes-le-Château is a large landmass floating in space that appears in Episode III, which Shion and her friends are asked to investigate at the behest of Juli Mizrahi. Resembling a valley of mountains and forests 70 kilometers in diameter, with a hemispherical bottom half, it appears as if it had been scooped out of a planet. Margulis claims that the mass is actually a portion of Lost Jerusalem, or Earth, that somehow appeared in space. Despite its abnormal location, there is consistent 1G gravity, breathable air on the surface, as well as a set of ancient ruins. Deeper underground lie a labyrinth of caves, stone passageways, an elaborate ancient temple, and abundant Gnosis. In the depths of this subterranean temple is a cross and burial site which looks exactly like the resting place of KOS-MOS' consciousness in the encephalon dive from Episode I. The name is from a castle in France rumored to be the center of numerous conspiracies, including the lineage of Mary Magdalene and Jesus Christ.