Digital cities can be abandoned and deserted, just like real-world ones -- and World of Warcraft is a prime example of this phenomenon, thanks to its many expansions.
Writing for the AV Club, Samantha Nelson details the hustle and bustle of World of Warcraft--and the cities players have left behind, as they leveled up and more cities became available to them:
These are perfectly preserved digital spaces, so unlike Detroit, they show no physical symptoms of their abandonment. But they are spaces designed for hundreds where it's possible to wander the streets without seeing a single other player. Computer-controlled characters will still cheerily train you in a new skill or peruse your wares, but the cities still feel desolate.
I go anyway. The emptiness feels appropriate in a place like Silvermoon. I imagine that the haughty Blood Elves discourage the other races from coming to their home. On the rare occasions when another player can be seen wandering the city's streets, it's almost always another elf. Maybe they're drawn back by an appreciation for the space's beauty. Without other players to distract you by dancing naked or generally bustling around the screen, a visitor can admire details like self-sweeping brooms and golems on patrol. These are the sights that make the place beautiful and magical -- and slightly ominous.
The entire thing is well-worth a read, especially if you're interested in a quick history lesson about how certain spaces in World of Warcraft are populated or deserted over time.
One of these abandoned spaces described is Shattrath -- which you can see concept art of at the top of this post, or, if you're interested, there's also an in-game screenshot by effysrponwyrmrestaccord that can give you a taste of what this city looks like:
Eerie, considering that MMOs are supposed to have a ton of people in them. But also kind of beautiful, eh?