EUROPE COMES TOGETHER BENEATH THE ALPS

After many years of hard work on the Brenner Base Tunnel project, the miners' attention is now trained on the rock faces – the thin layers of rock that separate Italy and Austria in the heart of the Alps.

Almost simultaneously, excavators equipped with breakhammers began operating in the east and west main tunnels of construction lot H53 Pfons–Brenner, carrying out the final stage of material removal.

Within about an hour, the final breakthrough had occurred in both tunnel tubes: through a cloud of dust, light shone through the new openings, marking the beginning of a new chapter in the history of the Brenner Base Tunnel.

The final centimetres – the long-awaited moment

And they're through! The historic breakthrough took place at exactly 10.35. Moments later, amid celebrations, miners and project managers entered the tunnel section on the other side of the national border for the first time, shaking hands with their Italian colleagues.

With this breakthrough, the Austrian excavation works of construction lot H53 Pfons–Brenner connected to the already completed main tunnels of the Italian construction lot H61 ‘Mules 2–3’.

At around 1,400 metres below the Brenner Pass, there are now two new cross-border connections between Austria and Italy.

After the breakthrough in the exploratory tunnel on 18 September last year, Austria and Italy are now also connected through the two main railway tunnels, having once again set aside the national border at the heart of the Brenner.

The moment when two construction sites meet

This significant event not only marks the completion of two tunnel sections, but also the convergence of two construction sites that have been working independently for several years: the Austrian H53 Pfons-Brenner construction lot and the Italian H61 Mules 2-3 construction lot.

Two different excavation methods were employed to reach this milestone. On the Italian side, tunnel boring machines (TBMs) Virginia and Flavia excavated the two main tunnels up to the national border. On the Austrian side, in contrast, excavation progressed using conventional methods and drill-and-blast techniques. Today’s breakthrough therefore connects not only two countries and two construction sites, but showcases two proven tunnelling methods.

This significant milestone represents far more than just an engineering achievement. It is a symbol of the close cooperation between the two countries, of engineering excellence and the unwavering dedication of all those involved in the project, who are bringing this railway infrastructure to life with expertise and commitment.

Today is a big day for the Brenner Base Tunnel project. Martin Gradnitzer and Umberto Lebruto, the two members of the BBT SE's Board of Directors, are celebrating the latest milestone in the project's history: "With the connection of the two main tunnels, our project has reached another major milestone. In the future, freight and passenger trains travelling between Austria and Italy will pass through here. This success is a remarkable demonstration of what can be achieved by working across borders towards a common goal. The project has many names, but above all it bears the signature of the people who built it day after day."

Precision is the key to success

This extraordinary achievement would not have been possible without the highest level of surveying accuracy. Consider, for example, the excavation of the exploratory tunnel: this was carried out using the most advanced measurement technologies from the Wolf and Mules access tunnels. At the time of the breakthroughs in September 2025, the recorded deviation was just a few centimetres. These extremely precise measurements then formed the basis for the excavation of the main tunnels, where the deviation at breakthrough was even smaller.

The real stars of this historic day are not wearing formal attire

The real stars of this historic day are not wearing formal attire. They are the miners, foremen, blasters, machine operators, electricians, surveyors, geologists, safety managers and engineers. These are the people who, for many years, day after day, shift after shift and metre by metre, have worked under the most challenging conditions deep within the mountain.

Michael Knapp, project manager for construction lot H53 Pfons-Brenner, says: "Tunnelling means facing new challenges every day. In this project, the mountain has constantly tested us by presenting us with unexpected tasks. I would like to express my sincere gratitude to the ARGE H53 contractor consortium (PORR and Marti), as well as to the local site supervision team, for their exceptional dedication."

Alessandro Marottoli, project manager for construction lot H61 Mules: "Today marks another historic day for the project. The fact that three tunnels now connect Italy and Austria with the Brenner Base Tunnel is a source of great pride for the entire BBT team, who work tirelessly on both sides of the border towards a common goal."

With today’s breakthrough, the focus is already on the future. The two TBMs, Wilma and Olga, are preparing to complete the excavation of the two main tunnels towards Innsbruck. Once these works are completed, all the railway tunnels will be fully connected.