Predator's Gold (Mortal Engines #2)

Tom and Hester, now in possession of the airship Jenny Haniver, which once belonged to an agent of the Anti-Traction League, find themselves being pursued by League forces. Scrambling to escape, they head north and land on the city of Anchorage, a small, non-predator city that traces its name back to old America. Anchorage's young ruler has decided that the wheeled city will make its way over the frozen wastes back to the Dead Continent, and the vicious predator city Arkangel is following along right behind. The savage Huntsmen of Arkangel are closing in, and the young margravine must make a last desperate bid for survival.