Southern Line

From the point of view of regional planning and the national economy, the main western line (to Salzburg and Passau) and the main southern line are equal in terms of the size of population and economic power of the respective regions served. The main western line, however, is a well-developed line (shortly to be a four-track line as far as Wels) connecting economic centres on flatland, whereas the main southern line has to climb above 900m above sea level three times (at Semmering, the Neumarkter Sattel and Kanaltal) on its way down to Carinthia and Italy; and routing in important sections is, technically speaking, antiquated (narrow radii, steep inclines).  Apart from that, a provincial capital - Graz - which is the second biggest city in Austria and the centre of an "automotive cluster", is situated along this route - but is completely off the beaten track. These facts contribute quite conclusively to diminish the importance of the main southern line; and the Koralmbahn project, together with the Semmering base tunnel, should deliver a decisive correction to this imbalance.

The inclusion of Graz in the planning of an uninterrupted line down to Carinthia was the subject of several surveys back in the time of the First Republic, and included the section across the Koralm mountains, however, did not plan for a long base tunnel: the resulting plan for a new mountain railway with huge gradients did not really have a chance of becoming reality. The upgrading of the old line via Maribor, which runs through the narrow, twisting Drau valley with its extremely steep slopes, was as unrealistic then as it would be today. This is a much longer stretch of track and would require, as a contemporary, upgraded line, a longer tunnel length than the route directly beneath the Koralm mountains. As such, this is also not a real alternative.

The pan-European rail axis from Warsaw to Bologna can be achieved as a high-speed and high-performance flat-level rail track - thanks to the Koralmbahn line and the Semmering base tunnel.