The Routes in the Game
You can select from a few different train lines in the game, sorted by region. The regions and routes in them are as follows:
Hokuriku Region
To the northwest of Tokyo, against the Sea of Japan is this mostly rural area. Although not snowy in-game, it's the area with the highest amount of snow in Japan.
Train Lines (in-game): Hokuhoku Line.
Tōhoku Region
To the north and northeast of Tokyo is an area with harsh climate known for being scenic and remote.
Train Lines (in-game): Akita Shinkansen, Ōu Main Line, Tazawako Line.
Kantō Region
The "center" of Japan. It includes the Greater Tokyo Area. Approximately one third of Japan's population live here.
Train Lines (in-game): Keihin-Tōhoku Line, Yamanote Line.
Kansai Region
Lies south/center-wise in the main island of Japan and includes the urban area of Ōsaka, Kōbe and Kyōto. Second most populated area in Japan.
Train Lines (in-game): JR Kōbe Line (Tōkaidō Main Line).
Tōhoku Region (bonus)
These are bonus routes for the Tōhoku Region.
Train Lines (in-game): Tōhoku Shinkansen.