WARNING: The following article contains spoilers from Batman: Earth One Volume Three by Geoff Johns, Gary Frank, Jon Sibal and Brad Anderson, on sale now.
The story of Earth One's Bruce Wayne is both similar and different to the one in the main DCU. Likewise, the characters and even the setting surrounding him are slightly different from the Gotham City fans know and love. This creates unique opportunities for a different take on how Batman would operate in unique scenarios. And in Batman: Earth One Volume Three, the Batcave gets a very different origin under another Gotham landmark.
While Wayne Manor did at one point connect to the Batcave, a police raid forced Bruce to move his base of operations to a subway station beneath Arkham Asylum. As it happens, the new Batcave shares similarities with the one that will be used in the upcoming movie starring Robert Pattinson as the Dark Knight.
The reason Bruce selected his new Batcave beneath Arkham Asylum was a multilayered one. First and foremost, it was convenient. Much like Wayne Manor, Arkham Asylum is not too close to the city to arouse suspicion should Batman be seen coming and going. And Bruce won't have to worry about legal issues because he owns Arkham Asylum. In this universe, Bruce's mother, Martha, is an Arkham herself, making Bruce the inheritor of the legacy of the Wayne and Arkham legacies. This came in handy to provide a suitable base of operations for his mission to protect Gotham.
The subway station itself was designed to connect the city to Arkham, making transit between the two easier. Due to the Arkham family's history of descending into madness, the subway was never opened. The Arkhams went so far as to intentionally design the pathways leading into the subway as a maze, hoping to confuse and trap the spirits they feared. This made it the ideal location for Bruce's new Batcave. It's remote and out of the way, legally his and almost inaccessible without working knowledge of the architectural layout.
In fact, Bruce and Alfred would not have been able to find the entrance to the station without the aid of Killer Croc. His knowledge of the tunnels beneath Gotham was vastly superior to Batman's, so he helped him find the correct path into the station. This is another major difference from the original Batcave. Batman knew of it, but could not find it without the assistance of someone else -- very different from the usual story of young Bruce falling into the cave.
Despite the differences to the main Batcave's origins, it does bear striking resemblance to what is known about the Batcave in the upcoming movie, The Batman. Much like on Earth One, Robert Pattinson's Batman will be operating outside of a train station. The words "Wayne Depot" have been spotted in trailers, revealing that the cinematic Batcave will be another property owned by Bruce's family. The architectural structure suggests that he is located within the city, unlike Wayne Manor or Arkham Asylum.
But even though Earth One's new Batcave is located in a different area, the choice of a train station as his new cave informs readers why it might actually be better than a traditional cave. For starters, the train station already has tunnels connecting it to the rest of the city. Batman is an industrious sort and would be more than capable of sealing off and creating secret passages into the rest of the city with enough time. And the fact that he owns the property means he can operate at his leisure in a space that seemed designed for his purposes.
If it is a coincidence that both the comic and the movie used a train station as a Batcave, then it is one that makes the case for them being better suited for the role than a literal cave.