Everyone knows what Gotham looks like: gargoyles, overhangs, and grey grey grey. Just look at the 90s Batman movies, or Batman: The Animated Series, or any of the Arkham games. But Gotham didn't always look like that - Batman '66 is a perfect example of that. So when did the change happen? Surprisingly, not until 1992. I could recount the story for you, but Comics Alliance did a great article on it a few months back, so I'll just link to it.