This chapter explores the changing shapes of British urban networks during the era of high industrialism. On the one hand it is a story of economic growth and decline; on the other it is a tale of adaptation and development, as many manufacturing towns added a range of administrative and cultural functions. The chapter discusses the urban interconnections and boundaries, town of Britain, region local systems, urban pathways: migration and technology, and networks abroad. Industrial urbanisation not only added great size to great density of towns in Britain, but major cities soon engulfed dozens of their small neighbours, which vanished into new boundaries and statistical categories. Particularly in industrialising regions, complex geographies of production, merchanting and finance arose on the basis of local social structures and regional ties. Before the Industrial Revolution, Britain had many towns, but only one city. London was and remains a primate city, whose size is sustained by its position in economic, cultural and political hierarchies.