One of my biggest faux pas with CIV has been the way cities are like islands unto themselves most of the time. In reality, most cities- though able to produce a great many products and provide for themselves a lot of basic resources- depend on each other for things each specializes in: Detroit builds cars, New York is a business hub, Kansas towns produce agriculture, Chicago makes pizza...
So really, every city depends on other cities to provide the things that are lacking.
In CIV, one the thing that always bothered me was the difficulty of sharing food between my cities. First of all, cities never actually produce any sizable quantities of food- the out lying rural areas do. But even at that, most cities these days don't even have 'outlying rural areas' in which farming can be done, and must have food shipped in from other regions.
I am just wondering how easy/difficult it is to share food and other resources between CivIII cities.