Route Ganymede is the train and road route primarily between the arcology of Kei Zentrum and Station Eisenzaam. It also serves as a secondary route to Station Gann Stelle through Route Marquise, though this route is normally only used for transit originating from Station Eisenzaam.

Beyond the crossroads of Route Ganymede and Route Marquise, Route Ganymede begins a descending grade for several hundred kilometers until Station Eisenzaam can be reached. When looking at Route Ganymede at a glance, a layman might assume that the spiral is completely nonsensical; maps do not normally show the depth difference obtained with this spiral, and therein lies the purpose.

By road or by train, the closer a traveler gets to Station Eisenzaam, the more the tunnels become replaced by massive welded plates of rolled homogenous armor. The last 200 kilometers on approach would begin to contain the first megastructure-level armor and shock absorbers built directly into the bedrock designed to withstand impacts from orbital bombardment and nuclear bunker-busters.