Agglomeration

Learn more about Agglomeration

In the study of human settlements, an agglomeration is an extended city or town area comprising the built-up area of a central place (usually a municipality) and any suburbs or adjacent satellite towns. Another term for agglomeration is urbanized area. However, because of differences in definitions of what does and does not constitute an 'agglomeration', as well as variations and limitations in statistical or geographical methodology, it can be problematic to compare different agglomerations around the world. It may not be clear, for instance, whether an area should be considered to be a satellite and part of an agglomeration, or a distinct entity in itself.

The Greater Tokyo Area provides an example of the difficulties involved because estimates of its population vary according to how it is defined. While the prefectures of Tokyo, Chiba, Kanagawa and Saitama are commonly used to define Greater Tokyo, the Japan Statistics Bureau simply measures the area within 50 kilometers of the Tokyo Metropolitan Government Offices in Shinjuku[1] [2].

The term 'agglomeration' is distinct from a 'Conurbation', which is a more specific term for urban clusters where the built-up zones of influence of distinct cities or towns are connected by continuous built-up development. Each city or town in a conurbation may nevertheless continue to act as an independent focus for a substantial part of the area.

A metropolitan area is an extended agglomeration or conurbation that also includes peripheral areas not themselves necessarily urban in character but closely bound to the urban area by employment or commerce.

The population may easily travel within an agglomeration by means of a cheap mass transit system. In other words, if one lives a thirty minute subway trip away from downtown New York city, and officially lives in a separately-named smaller district or town, that district or town would be considered a part of the New York agglomeration.

The term "agglomeration" is more appropriate for determining the populations of large super-cities like Tokyo, New York, and Seoul. These examples are super-cities which have expanded enough to consume other neighborhoods. Although administration may be separate for outlying districts, the population might say they are from the central city.

Currently, the largest agglomerations in the world are as follows: