Travelling from Northern Germany to Denmark’s capital Copenhagen is not as easy as it sounds. Trains either take the route through all of Schleswig-Holstein before then going east towards Copenhagen, or they board a ferry to go from Fehmarn to Lolland. But with the new Fehmarnbelt tunnel, the journey between Rødbyhavn and Puttgarden will soon be much quicker.

Germany and Denmark are working on a large infrastructure project together: The Fehmarnbelt tunnel will link the Northern German island Fehmarn with Rødbyhavn, allowing direct travel from Hamburg that is much quicker than before. Trains will take seven minutes and cars about ten minutes to cross the tunnel. There used to be a ferry to connect to the Southern Danish island of Lolland, but it was often affected by the wind and the weather conditions. Once the tunnel is completed, travel will be possible 24/7 and takes about an hour less than the ferry crossing.

The longest submersible tunnel in the world

Currently, only the first part of the tunnel on the Danish side has been built. Femern A/S, the Danish planning company tasked with the construction of the Fehmarnbelt tunnel, has initiated contracts for the portal and ramp facilities and completed a factory that will produce tunnel elements. On the German site, work began on the island of Fehmarn in spring 2021. A small-scale work harbour is already in operation, while the portal building and three new bridges for local traffic are expected by the end of 2024.

In June 2024, Danish King Frederik X inaugurated the first 217-metre section of the tunnel with a plaque at the entrance. Once the seabed trench is ready, this section can be submerged. It will lie at around 40 metres below sea level.

Sund & Baelt, the company building the Fehmarn link, has claimed that it will be the longest submersible tunnel in the world. The decision to build this underwater connection was already made in 2011, with work on the Danish side commissioned in July 2022 and on the German side in July 2023.

Refinancing the infrastructure with road traffic

While the mega project has attracted a lot of positive press, environmentalists have expressed concerns about the ecological impacts of the construction. Germany’s environmentalist organisation NABU has said that the Fehmarn Belt area, which is protected by the EU, might suffer damages in its biodiversity due to the construction process.

Femern A/S have responded saying that 300 hectares of new coastal wetlands will be created, as well as 42 hectares of new reefs at sea. This will create habitats for marine plant and animal life as well as new green corridors on land for insects, flora and fauna.  The impacts of construction will only be temporary, according to the Danish company, and utmost care will be taken to maintain the environment and its biodiversity.

Since the tunnel also offers four lanes for cars and trucks – two in each direction -, environmentalists are also questioning whether it meets EU specifications. “From what we understand, it’s not really a benefit for a change of transportation in Europe,” said Malte Siegert, head of NABU. “Especially not because Denmark wants to refinance the project with money from the road-traffic,” he added.

Opening projected for 2029

The most important impact of the new Fehmarnbelt tunnel will be the reduction in travel time. Whereas the ferry that once connected Fehmarn and Lolland took about 45 minutes, the new train will only take seven minutes to bridge the two countries. Across 18 kilometres, this link will support the transport sector’s green transition. It is set to open in 2029.

The Fehmarnbelt link will further contribute to interconnectivity in Europe. As part of the European transport system, it will support trade and economic growth. Denmark has also looked at other projects to build road-and-rail links to neighbouring Sweden as well as between two of its own islands.

In total, the link between Fehmarn and Lolland will consist of 89 concrete elements currently being constructed in Rødbyhavn. It is already dubbed as North Europe’s largest construction site. The total cost for the tunnel will be around 4.8 billion Euro (55.1 billion kroner). Users in Denmark will carry the cost, with the Danish government deciding details on the toll charge for the tunnel at a later stage.

Construction of the tunnel elements will continue until 2027. They will be submerged piece by piece from both sides of the tunnel and eventually connected in the middle. The opening of the crossing is projected for 2029.

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