Abstract
In order to apply the favourable one-way-street experience of the United States to a larger number of road networks, a scientific method is needed for determining the feasibility of unidirectional traffic flow in a road network of arbitrary geometry. The accessibility of one-way streets in road networks on arbitrary geometry is determined by utilizing topological concepts. Trees and impendent cycles are utilized to orient the roads of a unidirectional road network so that it is strongly connected. It is shown that any road network, excluding isthmuses and pendent edges, can be unidirectional and still be strongly connected. Evaluation of certain metric parameters in the topological graph of an arbitrary road network is suggested.