Abstract
Due to a diminishing role of public authorities in the financial support of public transport companies the question of what is an optimal network becomes more prone. However, the object of these companies, the maximisation of the revenues may lead to conflicts with the general objectives of the policy makers, such as maximal shift from car to public transport and maintaining the social function of public transport. Using these different functionalities it seems worthwhile to study the different networks that occur after optimization. In that way, more insight can be gained into the actual trade off between more revenues, less car kilometres and the accessibility of the public transport system.