major barrier between the two halves of the conurbation.
The river itself is lined with warehouses, office and
apartment blocks, and the occasional public building. The
bridges create links between the two edges, giving them
a particular significance. If you take a river bus in London
or Paris, you quickly become aware of the qualities the
river has as a corridor with firm urban edges.
Similarly, to drive along urban motorways is to be
aware of the edges formed by these vast concrete
structures that divide the city into huge parcels of land. A
study of how buildings interact with these barriers is
important to both the architect and town planner.
Roads often define the limits of our cities: a ring road,
for instance, may constitute an urban boundary – built up
on the city side and left green on the other. In sketching
boundaries the task of the artist is to search out examples
of continuity and discontinuity. Edges are best when they
are visually firm and well defined. One could perhaps
explore a river or motorway, noting and sketching strong
and weak points. Rivers often flow through fragmented
areas, such as older docklands, passing through to well-
regulated townscapes in the city centre. By selecting
particular viewpoints you can explore these physical
barriers, noting in the process areas where the edges
should be better defined, or where the barrier may be
bridged by some form of new structure.22.4
This courtyard house in Syria expresses
well the values of the society that it
serves. The courtyard house is a
relatively neglected domestic type.204 Understanding architecture through drawing