> we tend to talk about cities in heirarchical, enclosed terms, as having "limits",
Which is funny in a way, because people involved in the city-making business (for lack of a better term) have tried to do just that (i.e. imposing city limits) for centuries (at least).
The medieval city walls are a prime example of that, with anything that stood behind the walls treated as being part of the city and everything that was outside the walls seen as non-city, with non-city dwellers many times being required not to spend the night inside the city walls.
More recently, just the other day I was reading a transcript from a Romanian Communist party meeting from the late 1980s where the Romanian dictator Ceausescu (I'm Romanian and live in Romania myself) was complaining that cities have been let to grow indefinitely and with impunity, without respecting the city limits that had been set in law.
So you've got a late 20th communist dictator and Middle-Age burghers all trying to delay what I personally see as inevitable, i.e. the extension of the city by all means possible.
A little OT, but imo slightly related to this, there was a urban theory that was regarding as "proper" cities only those places with clear limits, for example the European Middle-Age towns, while the places with no clear limits set (many of those places located in the present Middle-Eastern Countries or in Northern Africa) were most of the times seen as "bigger villages", not as proper cities/towns. That was kind of a orientalistic/colonizing way of looking at things which I think stood behind the late 19th-most of the 20th century effort to make those Middle-Eastern cities look like their Western counter-parts, i.e. with clear limits set and with a clearer and more easily readable road structure.