Accessibility and Street Layout Exploring spatial equity in

neighbourhoods differ in a fundamental way from conventional town centres. The
difference is of a configurative one. These local centres demonstrate a nodal character
while traditional urban spaces have commonly a linear spatial organization.
The linear character of traditional urban centres has root to their gradual development
over time that stands in contrast to modernist neighbourhood units which were
planned and built at once. Linearity is crucial to accessibility since both geographically
and topologically reduces the distance to other places in a spatial organization. I
must stress here on the issue of scale. It might be claimed that even in the examined
local centres a linear character exists at the architectural level where shops and entrances
of different facilities are located next to each other shaping a linear pattern
on the very local scale. In fact it is true and centrality as an absolute node rarely happens.
But this is a matter of relativeness. On the scale of the neighbourhood where
for instance one has to walk around 600 hundreds meter to arrive at the local centre,
dimensions of the local centre do not count considerably.
Linear organization first and foremost recalls street as the axial element of urban
space. By linearity I intend to stress on what the local centres of our case studies lack.
But apart from spatial organization of the centre which partly contribute to accessibility,
the focus shall also be put on the way centre connected to the street network.
In this connection the concept of arteriality will be in introduced and discussed.
Arteriality
Arteriality is a feature of street system possible to recognize in any kind of street
structures. Arteriality as adopted here is taken from Marshal’s discussion of street
structure types (2005). He introduces two connected propositions: arteriality and
access constraints. Every network is shaped by a combination of these two features.
Generally speaking traditional urban structures tend to exhibit more arteriality
whereas in the modernistic ones access constrain appears to be more influential. Arteriality
highlights those streets act as the ‘necessary connections’ in a network. It is a
situation of strategic contiguity where all strategic streets yield a contiguous network.
Access constraint alludes to rules governing connections between different streets
in terms of controlling how each type of street is allowed to connect to other types.
Access constraint is epitomised in our case studies in terms of car access. Pedestrian
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