Imagine, if you will, a city of eternal night. A place so intensely crowded that sunlight never penetrates its alleyways. Overhead, wires dangle from the ceilings. Neon signs fizz in doorways. All around you, 33,000 people are crammed into self-built apartments barely 10m square, while overhead great airships rumble through sky. Is this a vision from the future? The setting, perhaps, for some dystopian sci-fi novel?