I have always wondered if the 'big productive urban center' (like London, or Paris, or Warsaw) is a boon or a curse for the 300 miles around it. Does it soak up young talent and capital from the surrounding areas, leaving the latter behind and exposed to deindustrialization, demographic problems and poverty? Or - through network effects in science, technology and productivity, does the metropolis create excess wealth that indirectly finds its way back into the rural areas, negating negative effects of the pull-effect? What are some good books on this topic?