Construction works kick off on the world’s longest immersed tunnel

The Femern Link Contractors joint venture began work on the world’s longest immersed tunnel last month.


Up to 9 metres high and 43 metres wide, the 18 km long combined road and rail tunnel linking Germany and Denmark will foster trade and tourism in Northern Europe.

Works have started on the Danish side, with the construction of the factory that will manufacture the 200-metre precast concrete box girders that will be immersed to form the fixed link between Denmark’s Lolland Falster region and Germany’s Schleswig Holstein Land.

Eric Tancré, Managing Director Infra and Dredging at DEME, said: “With the former infra marine activities of CFE firmly integrated within our Infra Activity Line, this large-scale infrastructure project is a great opportunity to jointly deploy our dredging and infra expertise, optimally exploiting the synergies of capabilities within the DEME Group. With strong partners in the joint venture, we aim for a successful and safe execution of the world’s longest immersed tunnel.”

The project will have a workforce of 2,000 employees at the peak of activity.

This new infrastructure facility, one of the most ambitious ongoing projects in Europe, will shorten the journey between the German and Danish coasts to just 7 minutes by train and 10 minutes by car from the current travel time of one hour by ferry or a 160 km detour by car.

Delivery is scheduled for mid-2029.

The joint venture comprises VINCI Construction Grands Projets (lead company for the two contracts covering construction of the immersed tunnel and the tunnel precast element factory), Per Aarsleff Holding A/S (lead company for the third contract, which covers the tunnel access ramps), Soletanche Bachy International (a VINCI Construction subsidiary), CFE, Dredging International NV, Wayss & Freytag Ingenieurbau, Max Bögl Stiftung & Co, BAM Infra and BAM International. Consultant: COWI.