Megaregion

Modern definitions

A megalopolis, following the work of Gottmann, refers to two or more roughly adjacent metropolitan areas that, through a commonality of systems—e.g., of transport, economy, resources, and ecologies—experience a blurring of the boundaries between the population centers, such that while some degree of separation may remain, their perception as a continuous urban area is of value, e.g., "to coordinate policy at this expanded scale". Simply put, a megalopolis (or a megaregion) is a clustered network of big cities. Gottmann defined its population as 25 million, while Doxiadis defined a small megalopolis a similar cluster with a population of about 10 million. America 2050, a program of the Regional Plan Association (RPA), lists 11 megaregions in the United States and Canada.