Atlantic Express train system which ran thru Rapture. The original system was created as the city was built (was used a great deal to transport material and workers to build the city). Later much of the system was rebuilt using a new improved AE_Mk2 design. Some sections of the old system remained (like the section in BS2 you ride across the Southern part of Rapture). The AE system was more equivalent to a subway system with Station stops relatively close together (City of Rapture is not more than 3 miles end to end). Symbolic Map of original AE System. The Mk1 System before Rebuilding ~1952 . .