Mainline is a track featured in MotorStorm: Apocalypse. The track itself consists of subway tunnels, drainage tunnels, a concrete canal, the city's central train station, a fissure created by the earthquake, an underground parking lot and a segment of collapsed highway (while the above-ground route is always available, the highway itself only collapses in the Festival Race). Trains will speed past in flames or may even fly off the rails and crash onto the track.
- Off the Rails - Day One, Midday - Destructive Events (Earthquake) - Mash
- End of the Line - Day Two, Midday - Destructive Events (Dusklite) - Tyler
- Mainlining - Day Two, Afternoon - Big Dog
- The track "Off the Rails" is featured in the game's single-player and mulitplayer demos.
- The term "Mainline" refers to a railroad's main track that runs throughout their network of rails. The opposite of a mainline is a 'branch line' which goes off in one direction and is a dead end, or connects to nothing.
- On portions of the track that feature railway tunnels and storm drains, it is possible to drive along the inside wall and ceiling. It is also possible to overtake larger classes such as the Big Rigs by utilizing this method. It is easiest to pull this off while driving classes such as superminis and buggies, but is impossible to do on ATVs, bikes, superbikes, and choppers because the game physics do not allow these classes to go upside down without wrecking. This is also required to get a Festival Card positioned on the ceiling of the tunnel.