Austrian Federal Railways (ÖBB-Infrastruktur AG) will invite bids in November for the second stage of the €2.3bn Koralm tunnel, a key feature of the under-construction Koralm line between Graz and Klagenfurt.

The 20km-long section forms the central stage of the 32.9km twin-bore Koralm tunnel. Construction is expected to begin by the fourth quarter of 2010.

The tunnel’s first stage on the Graz side has been underway since 2001 and the third stage on the western side will be put to tender in 2010.

The tunnel forms the last section of the €5.1bn 130km Koralm rail line, expected to open in 2020.

The 200kmph rail line will shorten travel times between Graz and Klagenfurt from the current nearly three hours to less than an hour.

The Koralm tunnel is also part of the trans-European transportation corridor VI stretching from Poland’s main industrial area to northern Italy.