Brenner Base Tunnel

The Brenner Base Tunnel is a 55-kilometre railway tunnel running beneath the Eastern Alps between Innsbruck in Austria and Franzensfeste in Italy. It will become one of the world’s longest railway tunnels when completed, surpassed only by the Swiss Gotthard Base Tunnel and possibly the Mont d’Ambin tunnel between France and Italy. Together with the existing Inntal Tunnel, the combined route will stretch 64 kilometres, forming the longest underground railway connection anywhere. The project replaces the steep and winding Brenner railway, which currently limits trains to speeds below 70 km/h. Once open, the journey from Innsbruck to Bolzano will shrink from two hours to just 50 minutes. The tunnel is part of the Berlin-to-Palermo Trans-European Transport Network and is funded jointly by Austria and Italy with major contributions from the European Union. Its completion is planned for 2032. The main tunnel starts near Innsbruck’s Wilten district and reaches depths of up to 1,720 metres below the surface in the gneiss section south of the border. About 60 per cent of the excavation work takes place in Austria, where 21 million cubic metres of rock will be removed. Spoil from the tunnel is reused to make concrete segments for the lining, reducing waste and transport. The northern approach includes two underground entrances beneath Bergisel and the Innsbruck bypass, adding 8 kilometres to the tunnel’s length. On the southern side, a new 180-kilometre line will run to Verona, mostly built underground. The project aims to shift freight from road to rail, cutting pollution in the narrow Alpine valleys. The existing Innsbruck–Bolzano railway, built between 1860 and 1867, has tight curves and steep gradients that limit capacity. The new line’s gentle 0.4–0.7 per cent gradient will allow trains to carry more than twice the weight of freight.