Service design and frequency setting for the European high-speed rail network

High-speed rail (HSR) is frequently seen as a promising alternative for long-distance travel by air and road, given its environmental advantages whilst offering a competitive level of service. However, a European HSR-network is yet to be realised, with the current state amounting to a patchwork of poorly connected subnetworks. Consequently, this results in a suboptimal performance from a user, operator and societal perspective. We present a customised version of the Transit Network Design and Frequency Setting Problem (TNDFSP) for the long-distance transport context and HSR in particular. We apply an adapted version of a heuristic solution approach to analyse the users', operators' and societal performance of a European HSR-network by conducting an extensive series of experiments to test the network's performance under various policy priorities and HSR design variables. Our experiment results show that designs resulting from the consideration of externalities yield more extensive networks with larger coverage and modal shifts. For such networks to materialise, high public investments are needed. The obtained network designs contain four different line types, exhibit spatial disparities in network density, and allow for the identification of potential hubs and critical infrastructure. The strong network integration with overlapping and border-crossing lines of substantial lengths highlights the importance of cross-border cooperation and rail interoperability. We hope our findings will contribute to the ongoing public and professional debates on designing an attractive and competitive European HSR-network.