At the edges of a district emerges a sufficient market to sustain the occasional corner shop, perhaps serving the needs of residents at the edges of two districts. Often, the edge of a new district begins to take form. In Johannesburg, perhaps subject to the worst excesses of the clearances that, even without apartheid, so changed the form of our inner cities, it is remarkable how these definable local districts consistently step through the city. Residents and the local economy A study of urban morphology often explains why traditional inner city areas have broken down. In Newtown, just west of Johannesburg city centre, and in Jeppestown to the south east, overlapping circles indicate a breakdown in urban form.
Communities wrestle with a legacy of clearance and a pre-eminence given to road systems.
Districts have insufficient residential density to sustain a local social and commercial economy. The distortion of evolved urban form also dramatically increases motor-vehicle dependence and further disenfranchises those without access to cars. Johannesburg's ongoing combi-taxi wars reflect the demand of millions of black Africans for an integrated public transport system. Another fundamental characteristic of sustainable local districts is that they have evolved with a direct relationship to the 'global' urban system. Social and commercial activity, given stability by local residents, is made more viable by access to through-movement and the wider market.