[1][2] It comprises a pair of tunnels running in parallel, each capable of carrying a single railway track, which will be linked together every 500 metres (1,600 ft).

In terms of international traffic, the completion of the line shall better facilitate the movement of rail freight between ports on the Adriatic and Baltic Seas.

[4] Prior to the construction process, extensive studies of the local geology were performed; during 2002, the first of a series of test bores, eventually totalling 130 exploratory wells, was driven in the vicinity of the future tunnel.

The excavation involved the removal of six million cubic metres of spoil, of which two-thirds was reused as bulk material for various noise barriers, railway embankments, filter gravel or aggregate in concrete.

[5] Other regional infrastructure projects have been impacted by the delayed completion of the tunnel, such as the doubling of the railway in the vicinity of Jauntal Bridge.