The idea of building a summit tunnel under the Brenner occurred to the Italian engineer Giovanni Qualizza as far back as 1847. But it was to be another 160 years before a base tunnel was built.

Construction milestones
20/08/2007Start of construction on the Mules access tunnel (Italy):
1.8 km, slope 9.3 %, cross-section 92 m², excavated by blasting
28/04/2008Start of mechanized excavation of the Aica exploratory tunnel (Italy):
10.5 km, with a double-shield tunnel boring machine (6.3 m in diameter)
23/10/2009Completion of the Mules access tunnel
04/12/2009Start of construction in Austria:
Sillschlucht (Sill gorge) exploratory tunnel: 5.4 km, cross-section 26 m², excavated by blasting
16/07/2010Start of construction on the Ahrental access tunnel (Austria):
2.4 km, cross-section 120 m², excavated by blasting
03/11/2010Breakthrough on the exploratory tunnel Aica-Mules
04/04/2011Start of excavation work on the Wolf I construction lot (Steinach am Brenner, Austria): logistic tunnels Saxen tunnel and Padaster tunnel
19/09/2011Start of excavation of the Ampass access tunnel (Austria):
1,350 metres in length, cross-section 35m², slope 10%, excavated by blasting
07/10/2011Start of construction work on the "Periadriatic Seam" construction lot (Italy):
3.7 km of main tunnels, 1.5 km of exploratory tunnel, contract amount 53.1 million Euro
24/06/2011Breakthrough on the Padaster tunnel (WOLF I construction lot, Steinach a.Br./Austria)
24/02/2012Breakthrough on the Saxen tunnel (WOLF I construction lot, Steinach a.Br./Austria)
11/10/2012Completion of the Ahrental access tunnel = Breakthrough on the access tunnel to the Sill gorge exploratory tunnel
01/07/2013Completion of the Ampass access tunnel
04/12/2013Start of excavation work on the Wolf II construction lot (Austria):
Access tunnel: 4 km, cross-section 120 m², slope 10%
spoil removal tunnel 950 m, works for the Padaster valley disposal site
11/12/2013Completion of the Sill gorge exploratory tunnel
22/04/2014Start of works on the Patsch shaft (Austria), 180 m, excavated by blasting
04/09/2014Completion of the Patsch shaft (Austria)
18/09/2014Start of excavation work on the Tulfes-Pfons construction lot (Austria):
380 million Euro, 38 km, Construction time 55 months
31/10/2014Start of works on the Isarco river underpass construction lot (Italy):
301 million Euro, 4.2 km of main tunnels, 1.8 km of connecting tunnels
14/02/2015Breakthrough on the 950 m spoil removal tunnel (Wolf II construction lot, Austria)
19/03/2015First blast on both main tunnels in Ahrental (Austria) in the presence of EU-Commissioner Violeta Bulc and the Ministers of Transport of the 7 Alpine States
25/03/2015Completion of the construction lot "Periadriatic Seam"
26/09/2015Start of mechanized construction of the Ahrental-Pfons exploratory tunnel (Austria):
17 km, 200 m open gripper tunnel boring machine (8 m in diameter)
22/12/2015Completion of the Wolf access tunnel
05/01/2016Start of excavation on the Wolf exploratory tunnel
06/12/2016Start of excavation work on the Mules 2-3 construction lot: 993 million Euro, 40 km of main tunnels, 15 km of exploratory tunnel, 10 km logistics and connecting tunnels, construction time 7 years
11/05/2017Tulfes- Pfons construction lot: Breakthrough east connecting tunnel
04/07/2017Tulfes- Pfons construction lot: Breakthrough west connecting tunnel
20/07/2017Tulfes- Pfons construction lot: Breakthrough emergency tunnel for the Innsbruck bypass
04/12/2018Breakthrough south portal in Fortezza
02/02/2018Start of excavation work on the Pfons-Brenner construction lot: 966 million Euro, 37 km of main tunnels, 9 km of exploratory tunnel, 6 km logistics and connecting tunnels, construction time 6 years
12/02/2019Tulfes-Pfons construction lot: Breakthrough Ahrental evacuation tunnel
29/03/2019Start of excavations on the "southern" exploratory tunnel from Wolf to Brenner
30/04/2019100 km of tunnels have been excavated
22/05/2019Mules 2-3 construction lot: Start-up of the last of the three TBMs excavating the Brenner Base Tunnel towards the Brenner
01/07/2019Start of excavations on the Pfons-Brenner construction lot
29/11/201950% of the excavation work on the Brenner Base Tunnel is complete
01/03/2020 Start of operations at Ahrental power station by Innsbrucker Kommunalbetriebe (IKB) and BBT SE
06/07/2020 Exploratory tunnel breakthrough in the Steinach am Brenner area
03/08/2020 Start of Sill Gorge construction lot - construction works taking place mostly above ground
15/10/2020 Isarco underpass construction site: start of excavations below the river
10/11/2020Isarco underpass construction site: first breakthrough below the Isarco river
08/02/2021 Isarco underpass construction site: relocation of the existing rail line completed
11/03/2021 Isarco underpass construction site: start of ground freezing for the first main tube
28/10/2021Start of the excavation works at the future northern portal: Innsbruck-Sill Gorge (western main tunnel tube)
24/11/2021Thanks to the tunnel boring machine "Serena", after 3.5 years and 14 km of excavation northwards, one of the BBT tunnel tubes reaches the state border at the Brenner Pass for the first time - 1,450 m below the earth's surface
04/05/2022Ground-breaking ceremony at the Hochstegen construction lot
19/05/2022With the breakthrough between the Mules and the Isarco River Underpass construction lots, we now have a continuous unbroken tunnel between the southern portal of the BBT and the State border at Brenner
07/07/2022Ground-breaking ceremony at the Sill Gorge-Pfons construction lot
30/03/2023Construction lot "H61 Mules 2-3": Arrival of TBM "Virginia" at the State border at Brenner - after 4 years and 14 km of excavation on the east main tunnel northwards
02/05/2023Construction lot "H41 Sill Gorge-Pfons": Start of mechanised excavation with TBM "Lilia" (10.4 m in diameter) for 8.1 km of excavation of the east main tunnel southwards
04/05/2023Construction lot "H53 Pfons-Brenner": Start of excavation work on 15.2 km of main tunnel using a TBM, 10 km of main tunnel using drilling and blasting, 1.3 km of exploratory tunnel, 2.6 km of cross-connecting tunnels, construction to last approx. 6 years, 959 million Euro
27/06/2023Construction lot "H41 Sill Gorge-Pfons": Start of mechanised excavation with TBM "Ida" (10.4 m in diameter) for 8.4 km of excavation of the west main tunnel southwards
04/12/2023Construction lot "H71 Isarco river underpass": Completion of the construction works
15/12/2023Construction lot "H52 Hochstegen": Completion of the construction works
17/09/2024Construction lots “H41 Sill Gorge-Pfons” and “H21 Sill Gorge”: First breakthrough of a main tunnel in Austria (eastern main tunnel)
18/09/2024Construction lot "H53 Pfons-Brenner": Start of mechanised excavation with TBM "Wilma" (western main tunnel) and "Olga" (eastern main tunnel) for approx. 7.5 km of excavation northwards, with a diameter of 10.4 m each

In 1971 the idea of a tunnel at the Brenner was dusted off again. The UIC, the International Union of Railways, commissoned a study for a new Brenner railway with a base tunnel. By 1989 three feasibility studies had been drawn up which formed the basis for further planning of the Brenner Base Tunnel.

This was the start of the planning activities. In 1994, the European Union included the Berlin-Naples corridor in the list of priority projects. Ten years later, Austria and Italy signed a State Treaty to build the Brenner Base Tunnel. In that same year, what is today the BBT SE was established. Construction work on the exploratory tunnel began in 2008.

Did you know …
... that the BBT is exclusively a railway tunnel?
Did you know …
... that both freight and passenger trains will travel through the BBT?
Did you know …
... that the BBT is one of the priority infrastructure projectes in the EU?
Did you know …
... that BBT SE is a public limited-liability company according to European law (legal structure "SE")?
Did you know …
... that the company's shares are held equally by the Republics of Austria and Italy?
Did you know …
... that the tunnel consists of two single-track main tubes?
Did you know …
... that the main tunnel tubes are already being built?
Did you know …
... that conveyor belts carry the excavated material underground to the deposits?
Did you know …
... that the BBT opens up the opportunity for more capacity for short-distance-traffic on the existing line?
Did you know …
... that the railway traction power supply is 25 kV 50 Hz?
Did you know …
... that the European-level signalling system ERTMS II will be installed?