UrsusArctos: 1300 meters is the deepest depth achieved by the Soviet submarine K-278 Komsomolets, the deepest diving military submarine ever built. Only specialized deep-diving submersibles go deeper. All this talk of depths and treating magma like water makes me wonder if Sandalphon was originally meant to be underwater rather than under magma. The references to the Kermadec Trench (10+ kilometers deep) in Nadia suggest that Anno and company are familiar with deep ocean trenches.
