If one followed the Gross Tar River from New Crobuzon to where it meets the Iron Bay fifteen miles later, one would run right into Tarmuth, the city’s principle satellite town. In many ways, Tarmuth is not a separate city, but a direct extension of New Crobuzon. Under the watchful eye of the Alderman, (a post appointed directly by the Lord Mayor of New Crobuzon,) the people of Tarmuth dutifully play their role in the great economic machine of the city. The town itself is long and narrow, following the shore a mile or so north and south of the estuary, split in two by the river.