London

Down they went and down, with Dog and Katherine following, down past the warehouse and on
down twisting spirals of metal stairs to the Digestion Yards, where Salthook was growing smaller by the minute. All that remained of it now was a steel skeleton, and the machines were ripping even that apart, dragging deckplates and girders away to the furnaces to be melted down.

Meanwhile, mountains of brick and slate and timber and salt and coal were trundling off on conveyor belts towards the heart of the Gut, and skips of furniture and provisions were being wheeled clear by the salvage gangs.

Chapter 2, Valentine, Mortal Engines, pg 15/152