Dome City 01

The idea itself revolves around a city on a colony planet that was once tucked under a dome while the planet was slowly terraformed. But once the planet's atmosphere has been stabilized, the dome shields were deactivated and the wall was slowly converted to an industrial belt and stripped off to an extent while the city extended much beyond the original wall. The wall is a central feature of the city, always visible and marking a clear separation of the older part (Ground Zero - G0), now a ghetto and the newer, larger parts of the city.