What’s the Difference Between a Megacity, a Metropolis, a Megalopolis and a Global City?
Historically, the size or population of a settlement was a general indicator of its importance—the bigger city, the more power it yields—however, with the large rural-to-urban migration of the last century, it has become harder to define what makes a city important.
Growth of a Great City from the Seeds of Ieyasu’s Edo
Tokyo is the largest megacity in the world according to The World’s Cities in 2016, a data publication from the United Nations. The Tokyo urban agglomeration—the metropolis itself, along with its surrounding urban sprawl reaching into the neighboring prefectures of Kanagawa, Saitama, and Chiba—has 38 million inhabitants, more than the population of Canada.