Megalopolis

Grouping of neighbouring metropolises

A megalopolis, also called a supercity or megaregion, is a group of metropolitan areas which are perceived as a continuous urban area through common systems of transport, economy, resources, ecology, and so on. They are integrated enough that coordinating policy is valuable, although the constituent metropolises keep their individual identities. The megalopolis concept has become highly influential as it introduced a new, larger scale thinking about urban patterns and growth.

From Wikipedia, under CC BY-SA. More on occurri.