photo: BBT / Public domain/The final blows of the breakhammer excavator
Austria and Italy have joined both main tubes of the Brenner Base Tunnel beneath the Alps. The breakthrough is historic, but the tunnel still needs years of work, and parts of the railway leading to it remain far from ready.
According to BBT, construction teams completed the final cross-border breakthrough in both main tunnel tubes on 28 July. The openings were made almost simultaneously, around 1,400 metres below the Brenner Pass. The event connected the Austrian H53 Pfons–Brenner construction lot with the completed Italian H61 Mules 2–3 section. Austria and Italy are now linked underground through the exploratory tunnel and both future railway tubes.
It is one of the most visible milestones in the project’s history. It is not, however, the end of excavation, nor does it mean that the main freight bottleneck between Germany and Italy is about to disappear.
Both Brenner Main Tunnels Now Cross the Border
The breakthrough took place at 10:35. Within roughly one hour, construction teams had removed the final rock in both tubes. The Austrian and Italian teams had approached the border using different methods. On the Italian side, tunnel boring machines Virginia and Flavia excavated towards Austria. The H53 consortium used drill-and-blast excavation from the Austrian side.
PORR said the crews worked through central gneiss at a depth of approximately 1,408 metres beneath the Geigenspitze. Rock temperatures reached around 30°C. Long underground transport routes added to the difficulty.
The Austrian lot excavated around five kilometres in each main tube. The permitted deviation from the planned tunnel axis was only a few centimetres. According to BBT, the actual difference at the breakthrough point was even smaller. "With the connection of the two main tunnels, our project has reached another major milestone," said BBT SE board members Martin Gradnitzer and Umberto Lebruto.
However, even though the two tubes are connected across the border, the tunnel system is not yet fully excavated. Tunnel boring machines Olga and Wilma still need to continue north towards Innsbruck. Only after they complete their drives will all sections of the main railway tunnels be connected.
What Still Has to Happen Before Trains Can Run?
The Brenner Base Tunnel consists of far more than two continuous holes through the mountain. Its full tunnel system will extend to around 230 kilometres once the main tubes, exploratory tunnel, cross-passages, access tunnels and other structures are included. After excavation comes the railway installation. The project still requires track, power supply, signalling, telecommunications, drainage, safety systems and operational testing.
The opening is planned for the end of 2032. Until then, contractors must complete the remaining excavation, fit out the tunnel and test the entire system under railway operating conditions. Once open, the tunnel should transform the most difficult part of the Brenner route as the existing railway climbs steeply over the pass and follows a winding alignment. Heavy freight trains often require two or three locomotives. Train length is generally limited to around 450 metres.
BBT says the new low-gradient route will allow 740-metre freight trains to cross with one locomotive. Freight trains should pass through the tunnel in around 35 minutes, compared with approximately one hour and 45 minutes on the existing line. Passenger trains should complete the section in about 25 minutes instead of one hour and 20 minutes. That will reduce traction costs and make railway operations easier. It will not automatically create a high-capacity corridor from Munich to Verona.
Read more
A family trip in Czechia went wrong when a train took off with a father and one child while his eight-year-old son was left behind on the p…
Germany’s Brenner Access Route Is Still in Planning
The biggest question lies north of the tunnel. Germany plans a new double-track railway through the Bavarian Inn Valley to handle additional freight and passenger traffic. More than half of the proposed line would run in tunnels.
However, DB InfraGO completed only the preliminary planning stage in July 2026. It has selected a preferred route and prepared the project for parliamentary consideration in the Bundestag. Parliamentary approval is required before detailed design, the formal approval process, procurement and construction can follow.
That leaves a clear timetable mismatch. The base tunnel is due to open in 2032, while the full German access route has not yet entered its final design and approval phases. The existing railway will remain available, but it already carries regional, long-distance and freight traffic. If the tunnel generates the expected increase in trains, capacity north of the Alps could become another issue.
Rather than an isolated project, the European Commission describes the Munich–Verona section, including the access routes, as the main bottleneck on this part of the Scandinavian–Mediterranean Corridor, meaning completing the tunnel removes the steep mountain crossing, but completing the corridor requires sufficient capacity on both sides.
The Current Closure Shows Why Access Lines Matter
The existing Brenner railway is currently experiencing the kind of disruption that the new tunnel alone cannot eliminate. From 17 July to 1 August 2026, long-distance trains cannot run between Innsbruck and Bolzano because of work on the Italian southern ramp. Replacement buses operate for passengers, while freight trains must take longer diversionary routes.
RFI is renewing tracks and railway technology at Brenner station and on the southern approach. ÖBB has used the same closure to repair frost damage and maintain its section of the route. Ten daily long-distance services to and from Italy are affected. Some trains are being diverted via the Tauern route and Tarvisio, while other passengers must change to buses between Innsbruck and Bolzano.
This closure is temporary and planned. Even so, proves that the new base tunnel cannot prevent disruption caused by maintenance, construction, or limited capacity on the routes connected to it. For freight operators, the value of the Brenner Base Tunnel will depend on the whole journey. A fast passage beneath the Alps has less impact when trains then wait for paths near Munich, Innsbruck, Bolzano or Verona.
Read more
DB InfraGO is changing how it responds to extreme heat after the disruption seen in June. From 30 July, railway operators across Germany will be able to…
What Freight Operators Stand to Gain
A flatter railway means fewer locomotives, lower energy use and the possibility of longer and heavier trains. It should also reduce the time and complexity involved in crossing the Alps. The European Commission has previously estimated that the Brenner project could help shift a significant share of heavy goods traffic from road to rail. The route forms the central Alpine link on the Scandinavian–Mediterranean Corridor, which connects northern European ports and industrial areas with Austria, Italy and the Mediterranean.
Yet infrastructure alone will not deliver that shift. Rail freight also needs competitive prices, reliable train paths, compatible operating rules, modern terminals and enough capacity beyond the border section. Construction works on one part of the corridor can quickly cancel out time saved elsewhere.
The present line closure makes that visible. Freight trains are being diverted over a wide area because one section is unavailable. The same network will need to absorb years of access-route construction before the full Brenner corridor is complete.