Located in the centre of the Alps at the lowest altitude compared to the other Alpine passes (1,371 m above sea level), the Brenner Pass has always been a transit and transport route of crucial importance for Europe. Today, the Pass is concerned by a fourth of the entire transalpine freight traffic.

The current Brenner railway line has now reached a high level of saturation and the pressure of the community and local governments is equally strong to transfer heavy traffic, which today takes place mainly by road along the Brenner motorway, with considerable impact in terms of air and noise pollution, to rail.

The intervention falls within the European TEN-T "Scandinavia-Mediterranean" Corridor, connecting Helsinki and Valletta, passing through Central Europe, the Tyrrhenian ridge and the main Sicilian cities, with a length of 9,400 km.

The central alpine part of this alignment consists of the Munich - Innsbruck North Access Line, the Brenner Base Tunnel and the Fortezza - Verona South Access Line. The North Access line and the Brenner Base Tunnel have cross-border sections, while the South Access line is located entirely in Italy, along the Isarco and Adige valleys.

The Brenner Base Tunnel will extend for a length of about 55 km between the stations of Fortezza (Italy) and Innsbruck (Austria), where it will be inserted underground into the existing bypass, also in a tunnel reaching an overall length of 64 km.

The South Access line will extend for a length of approximately 180 km between the stations of Fortezza (BZ) and Verona (VR) and will quadruple the current two tracks. The north end of the intervention consists of Lot 1 Fortezza - Ponte Gardena, which will mainly develop in a tunnel for a total length of 22.5 km.

The goals  

To increase the quantity and quality of the railway range, a new railway line is currently under construction to cross the pass: the Brenner Base Tunnel - by the European company BBT-SE “Brenner Base Tunnel - Brennero Basistunnel” to which the access line from the south, Verona - Fortezza will be connected, which will be built by RFI S.p.A. in lots.

Technological and infrastructural interventions will make it possible to increase the capacity of freight transport, which can be quantified in 60 - 90 more trains per day. The reduction of the constraints due to gradients will promote the use of longer and heavier trains with an increase in the transportable load of about 20% for each train. In addition to commercial speed, the standards of traffic regularity and punctuality will be raised.

Expected benefits

The keystone of the new performances will be the radical reduction of the maximum gradient: in the Brenner base tunnel it will be contained within 7 ‰, in the Fortezza-Verona line within 12.5 ‰, where the existing infrastructure has gradients which, reaching 26 ‰ along the pass and 23 ‰ between Fortezza and Verona, they limit train speed to within 80km/h in the most tortuous sections.

With the new works it will be possible to separate the freight traffic flows from passenger ones and, among these, long-distance services from local ones, with enormous benefits for passengers.

Local public transport will be able to take place on the historical line in a more efficient, faster and rhythmic way, while on the new tunnel section from Fortezza to Innsbruck, 20 km shorter than the current one, the times for drive change will disappear, now different between Italy and Austria, reducing travel time by a third for faster trains: from the current 75 minutes to 25 minutes.

On the freight front, the specialisation of the lines will allow an increase in traffic from the north entering the Verona junction, with a significant impact also for the Quadrante Europa intermodal road/rail terminal, increasingly key to the Italian and European logistics system as the intersection point of two European TEN-T Core Corridors, Scandinavia-Mediterranean and the Mediterranean, as well as the two Brenner (North-South route) and Serenissima (West-East route) motorways.

To prepare the terminal infrastructure for the future, a project was also recently launched which, by upgrading the existing railway infrastructure and through new technologies, will allow direct connection with the Brenner route, as well as with the railway line to and from Bologna/Mantua/Modena.

Benefits for the environment

The technical-constructive characteristics of the new railway connection, in particular linked to the drastic containment of the gradients and the underground passage of the line between Verona and Innsbruck, will allow to mitigate the noise impact linked to heavy traffic as well as to reduce the consumption of drive energy up to 40%, with parallel reduction of CO2 emissions.

The qualitative and quantitative increase in the railway range for freight transport together with the greater accessibility of the terminals in northern Italy that will derive from the entry into operation of the new railway works, will contribute to the achievement of the objectives set by the European Union Transport White Paper: transfer 30% of freight traffic over 300 km to rail by 2030 and 50% by 2050.

Main technical characteristics

Brenner Base Tunnel

  • two single-track tunnels, one in each direction, connected to each other every 333 m by cross tunnels
  • length from Fortezza to Innsbruck: 55 km
  • length from Fortezza to Tulfes: 64 km
  • maximum gradient: 7‰
  • design speed: 120 km/h for freight trains, 250 km/h for passenger trains

The Brenner base tunnel will consist of three bores: two main single-track tunnels spaced about 70 metres apart - and connected every 333 metres by cross tunnels - and an exploratory tunnel interposed between the two main tunnels at a lower altitude of 12 metres.

Overall, the Brenner base tunnel envisages the construction of 230 km of tunnels built by the European company BBT "Brenner Base Tunnel - Brenner Basistunnel BBT SE", 50% owned by the Austrian company "ÖBB Infrastrukture" and by the Italian TFB. The latter is controlled by Rete Ferroviaria Italiana S.p.A., the majority shareholder, and also includes the Autonomous Province of Bolzano, the Autonomous Province of Trento and the Province of Verona among the shareholders.

Project construction was divided into 6 lots, divided as follows from north to south:

In Austria

  • Gola del Sill: this is the lot near the Innsbruck north portal, currently the works have yet to be started. It mainly includes works on the surface.
  • Tulfes - Pfons: this is the northernmost lot of the work, currently under construction. It includes approximately 43.3 km of tunnels, including the 9.7 km long rescue tunnel parallel to the Innsbruck bypass.
  • Gola del Sill - Pfons: it is the lot that is inserted between the Gola del Sill to the north and the Pfons-Brenner to the south, currently the works have yet to be started.
  • Pfons - Brenner: the lot provides for the construction of approximately 50 km of tunnels and exploratory tunnel.

In Italy

  • Mules 2-3: this is the largest section of the Brenner base tunnel; it involves the construction of approximately 65 km between the Brenner and Mules and from Mules to the border with the Isarco River underpass lot. Once the Mules 2-3 lot has been completed, all the excavation works in Italy will be completed.
  • Isarco underpass: includes the section of the base tunnel which, passing through the bottom of the Isarco valley, developing for about 6 km, will underpass the Isarco river and the existing railway and road infrastructures (state road SS12, Brenner railway, Brenner). 

South access line 

  • length from Fortezza to Verona: about 180 km
  • maximum gradient: 12.5‰
  • design speed: 200 - 250 km/h

The southern access line quadruples the current railway line for the most part in variant with respect to the existing route. Project construction was divided into 4 priority lots, to be constructed by RFI, divided as follows from north to south:

  • Fortezza - Ponte Gardena section (lot 1). The project involves the construction of a new railway line, approximately 22.5 km, of which 15.4 and 6.3 km respectively for the two double-bore and single-track tunnels Scaleres and Gardena, which connect the Fortezza station to the Ponte Gardena station. The two new tunnels will be connected by a portion of the line in a viaduct over the Isarco river. The maximum gradient will be reduced from the current 23 ‰ to 12.5 ‰.
  • Bolzano railway bypass (lot 2). The railway bypass will make it possible to separate the flows of freight traffic from that of passengers (regional and medium-long distance). The railway shunt will also avoid the transit of freight trains in the town of Bolzano.
  • Trento and Rovereto railway bypass (lot 3). The railway bypass will make it possible to separate the flows of freight traffic from that of passengers (regional and medium-long distance). The railway shunt will make it possible to by-pass the urban areas of Trento and Rovereto. For the Trento bypass (Lot 3a) the new line will originate in Roncafort, near the Trento interport, to connect to the existing line in Acquaviva after about 14 km, of which about 12 km for the Trento double-bore single track tunnel. For the Rovereto bypass (Lot 3b), the new line will be mainly underground with the construction of the double-bore and single-track Zugna tunnel and will originate in Acquaviva to connect to the existing line in Marco, south of Rovereto.
  • Entry from the north into the Verona railway junction (lot 4). The new railway line, about 9.5 km, will run partly alongside the existing line and partly in a variant of the route. The design is being revised and integrated in the terminal part, at the San Massimo junction, to improve the overall practicality of access to the junction.

Work progress

Since the start of the works in 2008, over 136 of the total 230 km have been excavated for the construction of the Brenner Base Tunnel.

Following are the details of work progress for the access line from the south:

  • Lot 1: with Resolution no.72 of 27 July 2020 RFI approved the Final Variant Project of lot 1 Fortezza-Ponte Gardena. The call for tender was published on the EU O.G. in August 2020 and the award of the services is expected in 2021.
  • Lot 2: the preliminary design subject to project review was developed.
  • Lot 3: the preliminary design subject to project review was developed. Following the agreements with the local authorities, it is expected to complete the review activities within the first half of 2021, for the part relating to the Trento city bypass (Lot 3a).
  • Lot 4: the preliminary design subject to project review was developed. In agreement with the local authorities, the review activities are expected to be completed by the second half of 2021.

Workers employed

There are currently more than 1,200 workers involved in the construction of the work, as well as about 200 technicians engaged in the construction supervision and support services (environmental monitoring, topography, etc.) at the BBT sites, both in Italy and in Austria.

Investment and schedule

The total costs of the Brenner Base Tunnel are estimated at around 8.4 billion Euro, 40% co-financed in equal measure by Italy and Austria and 50% by the European Union.

The overall economic investment of the Verona - Fortezza line (for the 4 priority lots) is approximately € 5 billion.

The first excavation works for the exploratory tunnel of the Brenner Base Tunnel began in Aica in 2008.

For the start of work on the South Fortezza - Ponte Gardena access line, negotiations are currently under way for the integrated contract, which is expected to be completed within the first half of 2021, with consequent delivery of services.

The Southern Access Line, which falls entirely within Italy, will be completed by the end of the works on the Brenner Base Tunnel.