A
conurbation is formed when towns expand sufficiently that their urban areas join up with each other. This process has happened many times in the
United Kingdom, with
London being the most famous example of this type of development.
Green Belts were introduced in the
20th century to try to stop new conurbations forming.There is a spectrum that can be drawn between the conurbations that have a clear 'head' (such as Nottingham, Portsmouth, Southampton) to those that are do not - known as multi-centred conurbations (such as Bournemouth/Poole and Teesside) - via ones that are more borderline (West Midlands). In the case of the West Midlands, for example, the 'centre' city, Birmingham did expand massively and is now considered to include areas that were formerly independent towns, such as
Sutton Coldfield and
Aston. However, here it stopped, with the Black Country and Wolverhampton retaining strong identities.
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