A new rail link through the Alps passed a key milestone Sept. 18 when mining crews broke through the last diaphragm of a 57.5-kilometer (35.7-mile) exploratory tunnel connecting Italy and Austria. 

Overseen by owner BBT SE, an Austrian-Italian public entity established for the project, the Brenner Base Tunnel is intended to significantly shorten rail travel times through the Alps, and will tie the rail networks of Northern Italy into an existing rail line to Innsbruck, Austria. BBT SE says it will be the longest underground rail connection in the world when complete, and the first dedicated rail tunnel linking Italy and Austria.

Photo courtesy BBT SE

Dignitaries from Austria, Italy and the European Union were on hand for the event. “Today, Europe is growing closer together through Italy and Austria,” said BBT SE executive board members Gilberto Cardola and Martin Gradnitzer in a statement. “The past few years have been challenging, but as a management team we have made this milestone possible.”

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The project has slipped behind its original schedule and beyond its estimated budget. Currently, it is on track for completion in 2032, about 16 years behind schedule, and at a cost of roughly 8.5 billion euro, about 2.5 billion euro over budget.

When complete, the longest tunnel of the project will be 64 km. The exploratory tunnel completed this month runs below where the final tunnel will be bored. To date, roughly 200 km of tunnels for the Brenner Base Tunnel project have been excavated since construction officially began in 2008.

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