On 18 September 2025, the Brenner Base Tunnel celebrated the completed excavation of its exploratory tunnel which started in December 2007. Commissioner Tzitzikostas marked this important milestone in Brenner, together with Mr Matteo Salvini, Italian Minister for Infrastructure and Transport and Mr Peter Hanke, Austrian Minister for Climate Action, Environment, Energy, Mobility, Innovation and Technology.
The 56 km long excavated exploratory tunnel runs between and below the two main railway tunnels and provides information on rock mass which will reduce costs and time for the construction of the main tunnels. Once the Brenner Base Tunnel becomes operational the third exploratory tunnel will be essential for drainage, for the installation of technical equipment and for maintenance works.
All excavation works planned on the Italian side have also been completed in 2025. By August 2025, 88% of the Brenner Base Tunnel excavation was completed. The EU has financed the Brenner Base Tunnel from the early phases of feasibility and environmental studies under the TEN-T programme to further studies and construction works under the CEF Transport programme. The total EU contribution planned until the end of 2025 amounts to €2.3 billion.
State of play
Out of seven construction sites, three sites are active: two in Austria and one in Italy. Key achievements include:
- Lots completed:
- Lot H71 Isarco river underpass: completed in December 2023. Connects the base tunnel with the existing Brenner railway line and the Fortezza station. Overall, 4.5 km of main tunnels and 1.2 km of interconnecting tunnels to the existing railway line were built.
- Lot H52 Hochstegen: completed in December 2023. Excavated 4.8 km for the exploratory tunnel, main tunnels, connecting tunnels and cross-passages.
- Lot H33 Tulfes-Pfons: completed in September 2021. Excavated 43.3 km for the emergency tunnel, main tunnel tubes and exploratory tunnel.
- Lot H21 Sill Gorge completed in December 2024. Connects the northern end of the Brenner Base Tunnel and the central station in Innsbruck.
- Lot H61 Mules 2-3: works started in 2011 and excavation of the main tunnel and exploratory was completed in August 2025. In total, 65 km were excavated for the main tunnels, exploratory tunnel, crosscut and access tunnel. All the excavation activities of the Brenner Base Tunnel on the Italian side have been completed. Final lining is ongoing.
- Lot H41 Sill Gorge-Pfons: works have been ongoing since January 2022. In total, 22.5 km of main tunnel tubes and 38 cross passages with a total length of 2.3 km will be excavated. The two tunnel boring machines ‘Ida’ and ‘Lilia’ have already excavated more than half of the planned tunnel stretches.
- Lot H53 Pfons-Brenner: works started in May 2023. The two tunnel boring machines will drive a stretch of 7.6 km (a total of 15.2 km) in each main tunnel tube. The boring machines ‘Wilma’ and Olga started excavating northwards in September 2024. The lot is expected to excavate 25.2 km of main tunnel, 1.6 km of exploratory tunnel and 2.6km of cross passages.
About the Brenner Base Tunnel
The Brenner Pass, located between Austria and Italy, is one of Europe’s busiest mountain crossings used for freight transport. Each year, more than 2.5 million trucks, 14 million vehicles and 50 million tonnes of goods cross the Alpine pass. The new Brenner Base railway tunnel, co-funded with €2.3 billion from the CEF Transport programme, aims to ease congestion on the Munich-Verona route, which is part of the Scandinavian-Mediterranean Corridor that stretches from Helsinki to La Valletta.
The current railway follows a route established in 1860, winding up the 1,371-m-high mountain road with steep slopes of up to 26% incline. This design limits train speed and maximum load capacity, requiring at least two locomotives on the Italian side and three on the Austrian side. As a result, the existing railway is not competitive for cross-border freight or passenger transport.
The new Brenner Base Tunnel addresses these issues on the most critical part of the stretch by providing a nearly flat, straight route. At 64 km, it will be the world’s longest underground railway tunnel. With slopes of only 4 to 7 %, it runs 580 m below the Brenner Pass. The tunnel will reduce the Fortezza - Innsbruck line by 20 km. In the planning phase, freight trains were estimated to reach speeds of 160 km/h, and passenger trains up to 250 km/h, cutting travel time from 80 to just 25 minutes.
The Brenner Base Tunnel will consist of two single-track tunnels, each 8.1 m wide and spaced 40 to 70 m apart. Traffic through these tunnels will be one-way, and they will be connected with bypasses every 333 m for safety. To the south, the new line will connect to Fortezza via two single-track tunnels. To the north, it will link to the Innsbruck bypass and the lower Inn valley railway, as well as to Innsbruck railway station.
More information is available on the project website.
Last updated: September 2025
- Project locations
- AustriaItaly