The Iron Council - China Miville

With economic slump and growing social unrest, New Crobuzon has become a fraught and dangerous place. The militia patrol in uniform, there is tension between its myriad races, there are even rumours of war In an attempt to spur trade, a major company is building a railway across the continent, but the project involves brutal suppression of both the workers and the native inhabitants they pass. As mutiny grows among the slave labourers, one train is hijacked on the half-finished line. They tear up the track for a few miles behind them, then begin to rebuild it in front of the train - diverging from the original route and disappearing into the desert. This renegade train, 'The Iron Council', soon becomes an icon of freedom to the repressed urban population, till the city government has no choice but to hunt it down and destroy it. Whatever happens, they cannot allow it to escape...and so begins a desperate pursuit across alien wild lands filled with bizarre populations, monsters and hazards.