In the former post, The City Limits I: The City Itself, I talked about the ways of understanding the physical limit of cities. In this post, I still want to talk about the city limits but from a different point of view, not related to physical dimensions. In this case I want to talk about the intangible limit of the cities or the city hinterland.
In the last post I argued about the physical possibilities of mobility as the key factor to consider the limit of the city itself. But apart from the physical occupation of the land, it is true that cities have a bigger influence. For example, if we are talking about the world cities network we can see how there is a small number of cities that form part of this network, while the rest of the cities are just serving the principal nodes. We can see it clearly if we look at airports networks. Those main cities (known by everybody) which have the international connections are the world nodes and have the power to connect people from all over the world. That is an interesting key point, because again we are linking the physical possibility of moving and the transport ways of doing it.
We can also talk about the influence of cities economy. I have made an easy exercise, taking the 2008 GDP of several cities (PricewaterhouseCoopers UK Economic Outlook November 2009) and countries (Wikipedia). I have related the GDP of some mayor cities with their countries GDPs. The result is the following:
- New York City 9,6% of USA GDP
- Madrid 16,7% of Spain GDP
- Paris 22,1% of France GDP
- London 25,0% of United Kingdom GDP
- Tokyo 27,4% of Japan GDP
- Mexico D.F. 37,5%of Mexico GDP
These figures show how important is the mayor cities economy in the national (and in the international) level. We can also talk about political importance. To instantiate this reality I have found the following figure from Taylor et al. In the figure we can find a world formed through the great metropolis, but as decision centers who finally are the places which are ruling the world.
These three examples that I have exposed are another way to understand the city limits apart from their own physical limit. As we have seen, the holistic vision of the world as a sum of the biggest cities and not as a sum of countries is based in heavy foundations that guide us to understand their political, economic and connecting importance. So if in the former post we have said that the city is limited by the mobility possibilities, in this post we can say that, maybe, the cities have no limit if we understand them as the network where things happen in this world.