Ilium
You do not find Ilium on a map; you stumble upon it when you are seeking shelter from the acidic rain that falls perpetually on the plains. The city presents itself not as a gate but as a breach in a long wall of rusted corrugated steel, a wound that invites you to enter.
Within, the avenues are paved with shattered brick and the buildings sag into one another for support, their shared weakness a form of strength. A smell of wet wool and burnt oil hangs in the air, the scent of damp, enduring life. The few inhabitants move in small, tight circles, their paths worn into the ground like grooves; they trade in scavenged copper wire, in warm blankets, in stories told around fires lit in perforated oil drums.
From the outside, you might see only a city in collapse, a monument to rust and decay. But from within, the walls do not keep intruders out; they hold a chosen few together. Ilium was built to fall apart, but in a way that creates small, warm pockets for those who have learned to live in the cracks.