So once upon a time I made a whole city. It was all modular and had road networks, skyscrapers, smaller industrial buildings, construction sites, outer suburbs etc etc. The city had to be as efficient on polycounts as possible, so it looks a little simplistic. It was a modular style construction for Hurtworld, which was going to be a playground for more urban type adventures.
We had so many hopes for this, but alas it was not used in it's entirety. We did use some of the buildings as set pieces here and there. Turns out that in an Sandbox type game that aims to be playable on low spec PC's this was unfoirtunately too heavy for the game.
This entire city was textured from one 4096x4096 texture sheet. We didn't have an atlasing system yet, so to save drawcalls we decided to go with one large texture.