Ginnunga Gap

In Norse mythology, the Ginnunga Gap was an abyss beneath the bifrost of Valhalla. Much as mercury flowed through a TARDIS, the river Elivâger went down the Gap. When Ace viewed the Crevasse of Memories That Will Be from the astral plane, it bore resemblance to the Ginnunga Gap. (PROSE: Cat's Cradle: Time's Crucible)