Enhancing the productivity of the national railway systems is now one of the main concerns of transportation authorities in Iran. In this regard, one of the strategies devised by Iran's Railway Company is to increase the robustness of the system against incidents. The paper describes the state of the network and discusses that human errors are the main cause imposing significant costs. This is followed by the development of a method for the network vulnerability analysis of sparse interurban rail networks considering transportation of various goods as well as passengers. The paper examines the effects of an incident where consequent effects are substantial and propagate functionally throughout the network, to take the network closure duration into account, and to tie together both additional costs of transporting passengers/goods (due to prolongation of routes) and unsatisfied demand. The purpose is to find the most important links of the network, where failure results in serious consequences. Passenger unsatisfied demand, freight unsatisfied demand, and monetary costs are considered as the consequences of network disruptions, and a multi-objective optimization programming approach is designed to generate solutions based on these criteria.
