Brenner Base Tunnel Main Tubes Connected
PORR AG and MARTI have successfully connected the western and eastern main tubes of the Brenner Base Tunnel (BBT) near the Austrian-Italian border, marking significant progress in constructing Europe's longest underground railway tunnel.
Vienna, Austria – Construction firm PORR AG announced on July 28, 2026, the achievement of a major milestone in the construction of the Brenner Base Tunnel (BBT). The ARGE H53 consortium, comprising PORR and MARTI GmbH, successfully connected the western and eastern main tunnel tubes in the Pfons–Brenner construction lot near the Austrian-Italian state border.
This breakthrough links the tunnel sections excavated from the Austrian side to the already completed main tubes of the Italian construction lot H61 Mauls 2–3. The project, initiated approximately six years ago, has progressed at a depth of around 1,408 meters and an altitude of about 794 meters above sea level.
The tunneling efforts have faced challenges, including rock temperatures around 30°C and demanding geological conditions within the hard central gneiss, alongside lengthy transport routes. High precision was crucial, with deviations from the planned tunnel axis limited to a few centimeters over more than 5 kilometers, ensuring the accurate meeting of the Austrian and Italian tunnel sections.
PORR AG CEO Karl-Heinz Strauss highlighted the dedication and expertise of the workforce operating under difficult conditions. While this breakthrough permanently connects the two countries underground, several construction phases remain.
Upon completion, the Brenner Base Tunnel, one of Europe's most significant infrastructure projects, will become the world's longest railway tunnel at 64 kilometers. It is designed to shift a substantial volume of freight and passenger traffic across the Alps to rail, promoting sustainable transportation in Europe. Work continues towards Innsbruck, bringing this key European project closer to completion.