From the back of the book:
The Clanking City details Zistorwal: part factory, part fortress and vital instnument of the God Learners in their efforts to further their unique magical ends. Under smoking towers, the citizens stride among machinery built upon stolen secrets and enhanced by God Learner magicians and engineers. ThrOugh the streets strides a giant automaton; the auatar of Zistor, the man-made god. In underground surgeries, devout Zistorites replace their weak mortal flesh with alchemically-treated mechamagical implants. Rising from blood-stained tables bearing metal limbs powered by sorcery and clockwork.
This is the Machine City, known as the Clanking City for the noise its thousand engines make, and it stands defiant against a great siege mounted by the Empire of Wyrm's Friends and their allies of convenience. Within these pages you will find an in depth description of Zistorwal at the peak of its golden age, detailing the city itself, the movers and shakers of its twisted politics and its quintessential tools, from cunning mechamagics to towering war constructs.
The Clanking City allows players and Games Masters alike to experience Zistorwal at the height of its prominence, but be careful; something dark and terrible coils around its heart...