Semmering Base Tunnel holed through, passenger service due 2029

The Semmering Base Tunnel is a 27.3 km twin-tube railway tunnel between Gloggnitz (Lower Austria) and Mürzzuschlag (Styria) that will replace the existing mountain section of the historic Semmering Railway. Construction began on 25 April 2012 and the final tunnel breakthrough was achieved on 29 November 2024; total costs are estimated at about EUR 3.9 billion (as of 2022). Test and training runs are planned for 2029, with regular passenger service set to start at the December 2029 timetable change (the source list's rough target year was 2030). Update (20 May 2026): For the first time, an official delegation led by mobility minister Peter Hanke and ÖBB CEO Andreas Matthä has driven through the whole tunnel from Gloggnitz to Mürzzuschlag, still in minibuses rather than on rails. ÖBB now names the end of 2029 as the timetable for the first train runs through the tunnel, which would link Vienna and Graz in about 1 hour 50 minutes. Work has concentrated since summer 2025 on fitting out both tubes with track, cabling and other systems; because of the tunnel's dimensions this takes more than three years. (LOK Report, 20 May 2026)