The Golubinja Tunnel in Bosnia and Herzegovina, stretching 3.6 km between Žepče and Zenica, is the country’s longest road tunnel and a key part of the Pan-European Corridor Vc. Completed in stages with EU and international funding, it will significantly cut travel times and boost regional connectivity by 2026.

Tunnel (Predor Karavanke is a motorway tunnel crossing the Alpine Karawanks mountain range between Austria and Slovenia, with a total length of 7.864 km enclosure between the portals. It Karawanken Autobahn (A11) from Villach with the A2 motorway leading to Kranj and Ljubljana in Slovenia.

The "H53 Pfons-Brenner" construction lot comprises 25.2 km of main tunnels, which will be driven between the municipal area of Pfons and the national border at the Brenner Pass.

Bypakke Bodø is a collaboration between Bodø municipality, Nordland county council, the Norwegian Public Roads Administration and the Norwegian Railways to achieve important projects for pedestrians, cyclists, public transport and road traffic in Bodø.

Storage power plant Kühtai Tirol/Austria.

Protan has delivered Ventiflex to the KER450 tunnel project in Switzerland. Around 5.000m ducts in diameter 1.300mm.

Tunnel ATCOST21 / Germany

Tunnel S3 Bolkow / Poland

Ventiflex provide fresh air into the Bosphorus Strait tunnel through the construction process.