Italian Leg of Brenner Base Tunnel Reaches Austrian Border

The Webuild-led consortium has achieved a significant breakthrough in one of Europe’s most ambitious infrastructure projects. On May 9, 2025, the tunnel boring machine (TBM) “Flavia” completed its journey through the Italian side of the Brenner Base Tunnel, reaching the Austrian border. This accomplishment marks a crucial milestone in the construction of what will become the world’s longest railway tunnel under the Alps, revolutionizing transport between Northern and Southern Europe.

A Game-Changing Infrastructure Project

The Brenner Base Tunnel represents a transformative solution to one of Europe’s most congested mountain crossings. When completed, this 64-kilometer underground railway will connect Fortezza in Italy to Innsbruck in Austria, running beneath the Brenner Pass.

The current route, established in 1860, features steep slopes of up to 26%, making it inefficient and environmentally burdensome. Over 2.5 million trucks and 50 million tonnes of goods cross the Alpine pass annually, prompting urgent calls for a more sustainable freight transport alternative.

The Recent Breakthrough

The breakthrough of TBM “Flavia” is a major milestone. According to Webuild, Lot Mules 2-3 on the Italian side is now over 95% complete. This follows TBM “Virginia”’s earlier success in 2023.

“This work site… reflects the vision of two countries – Italy and Austria – with the support of Europe for a strategic project,” said Pietro Salini, CEO of Webuild.

Engineering Marvel: Technical Specifications

Length: 64 km (with 55 km under the Alps)
Design: Two single-track tunnels, 8.1 meters wide, 40–70 meters apart
Safety: Bypass every 333 meters
Grades: Reduced to 4–7% (from previous 26%)
Speed: Passenger trains – up to 250 km/h; Freight – up to 160 km/h
Time saved: Travel between Fortezza and Innsbruck will drop from 80 minutes to 25 minutes

This design enables safer, faster, and more energy-efficient rail operations across the Alps.

Economic and Environmental Impact

As highlighted by CINEA, the tunnel is a keystone of the EU’s Trans-European Transport Network (TEN-T). It is expected to shift freight from road to rail, reducing CO₂ emissions and easing congestion.

European Cooperation and Funding

The EU has contributed €2.3 billion via the Connecting Europe Facility (CEF), with a €700 million boost secured in 2023. This raised the EU’s funding share to 50%, with the rest equally split between Italy and Austria.

Details of funding are available on the official BBT-SE portal.

Cross-Border Challenges and Diplomatic Dimensions

The project operates in a complex legal and political environment. In 2024, the European Commission ruled that Austria’s traffic bans on the Brenner Corridor violated EU free-movement principles (Articles 34 & 35, TFEU), reinforcing the importance of seamless cross-border transport.

Looking Ahead: Timeline for Completion

With excavation nearing full completion and integration works underway, the tunnel is set to become operational by 2032, positioning itself as a central axis in the Scandinavian-Mediterranean Corridor.

As noted by Railway PRO, this tunnel isn’t just a feat of engineering—it’s a symbol of European unity, environmental responsibility, and sustainable infrastructure development.