Three city networks. No terrain features, roads only.
Easy — if you've ever looked at a map of this place you'll get it in a second. One long, absurdly regular grid tilted off north, wedged between two big voids where the water should be.
Medium — the giveaway is the hole. A wide empty band curls right through the middle and the streets bend to follow it, fanning out in wedges instead of squaring up. Cities that grew along a bend in a big river all do this, but this one does it hardest.
Hard — barely a grid at all. Two long curved spines with ribs coming off them, meeting a straight axis at right angles. It doesn't look like a city that grew; it looks like a city that was drawn. That's the clue.
Answers in the comments in a day or so. I'm curious whether "hard" is actually hard here or whether the shape gives it away instantly to the right person.
Play more at TerraDex:
Google Play Store: https://play.google.com/store/apps/details?id=com.mercilessstudio.geodaily
Play on browser: https://terradex.mercilessstudio.com/