CONCLUSIONS
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modes (such as public transport). By focusing on key ‘active ingredients’ such as speed and network coarseness, rather than on individual vehicle type, this is intended to accommodate and even promote (rather than exclude or discourage) participation of unconventional and novel modes. This should increase choice, and potentially boost efficiency and attractiveness of more ‘sustainable’ modes. The resulting system effectively integrates walking (and other access modes) with the public transport system, as a priority, rather than simply being the lowest rung in the vehicular hierarchy. To operationalise the ‘transit-oriented hierarchy’ implies optimising public transport patterns with respect to the urban street network (and the inter-urban network beyond). This book has suggested a possible starting point in principle, with suggestions for levels in such a hierarchy. To realise this will mean taking the theoretical concept of arteriality and interpreting and expressing this in practical terms for the purposes of planning the public transport service network. This will mean ensuring that strategic routes and services connect up; this is not only a matter of road layout, of course, but implies coordination across modes, infrastructure providers and operators.
Town planning The general topic of town planning has been somewhat peripheral to this book, since the main focus has been on certain topics relating to transport and urban design (and, even then, substantial areas of transport and urban design have not been addressed at all). In one sense, therefore, town planning is perhaps a discipline barely touched by the concerns of this book. However, in another sense this book could present a challenge to town planning orthodoxy, perhaps precisely because the investigation has suggested the possibility of generating urban structure without reference to the overall urban outcome – in other words, creating towns without plans. What is at stake is the basic organising unit of spatial structure. The street-based approach suggested in this book effectively puts the topology of the line of movement ahead of the topology of the area – such as the land use parcel, zone or neighbourhood – which has been the conventional spatial basis for town planning. In effect, it would be possible to have a system of spatial organisation based wholly on the structural organisation of routes, where route types had land uses built into them – rather than the other way around. In this sense, the primary determinant of land use would be the street type, not the land use zone. Moreover, the street-based generation of urban structure is a constitutional approach, in which only local elements and relationships are