(Up to: The Many Faces Of Reality Hacking )

The design of a city is literally a concrete example of the way in which our actions are guided and enforced through a designed infrastructure. There are 2 sides to this. Firstly, we must understand the reasons behind these designs, and why they exist - namely, in order to keep a semblance of order in a system that would otherwise shift into chaos. Humans aren't very good at dealing with chaos, and their natural instinct for order over collectives of people lead to these designs, and the propulsion of their construction into both an art and a science. As we live in a world designed by humans and are humans ourselves, thus we have to understand that these designs are, on the whole, for our own benefit.

Secondly, having realised this, we can begin to work out the "gaps" in these designs. That is to say, there is an obligatory rule in city design that says any part of the city must be accessible somehow, as there wouldn't be much point in having a place where you couldn't get, in such a tightly-packed space. OK, that's a broad generalisation, but as we're conforming to the human element anyway, there's also no point in trying to get to places that aren't of any use either. The two therefore go hand in hand - if we want to get somewhere useful/interesting, then there must be a route to it.

Now, it may be then that this route is not the route offered to us by the natural flow of the design, at which point things get a little more relevant.
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This can be applied on many scales - from walking round a corner, to getting a truck from one place to another.

See also:

• The Art Of The Environment - Transcending time to visualise urban flow