The DC Universe is home to several cities that don't exist in real life. Fictional locations allow creators greater freedom to build their settings without being confined to geological accuracy, and design them to represent specific themes. Readers can more easily identify with universal locations when they can impose their own experiences. Not to mention, these cities also act as containment fields for big battles that small towns or suburbs aren't equipped to handle, since villains usually flock towards heroes like moths to a flame.

Marvel Comics intentionally opted instead to set their characters in real-world locations to differentiate themselves from the more imaginary world of DC Comics. The JLA/Avengers crossover from 2003 canonically established that DC's Earth is slightly larger in mass than Marvel's Earth to accommodate the extra cities along the East Coast. One could reason that the DC Universe is farther away in the Multiverse, which is unfortunate because it's home to several unique cities that would be fascinating to visit.

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Fans have seen a few different versions of Gotham City over the years, from Batman's main comic version to film and TV variants in shows like Gotham.