The first element of the Fehmarnbelt tunnel successfully immersed
After a multi-day operation, the first of a total of 89 concrete elements for the Fehmarnbelt tunnel is now in place on the seabed. The historic event began late on Monday evening, 4 May 2026. Five tugboats and the special immersion vessel IVY transported the tunnel element from the tunnel factory at Rødbyhavn on the Danish island of Lolland to the immersion point off the Danish coast.
Around noon on Wednesday, the immersion itself began. Approximately 14 hours later, the dedicated position in the Fehmarnbelt had been reached, and the first tunnel element had been positioned precisely in the tunnel trench in front of the Danish tunnel portal. Subsequently, the element was connected to the portal using hydraulic arms. The position was then finally confirmed by precise laser measurements inside the immersed tunnel element. Later in the day, IVY will then be released from the element.
Next, the two immersion pontoons will be towed back to the work harbour. They will be replaced by another special vessel, which will place large quantities of gravel along the sides of the element. This ensures it remains securely in position.
This is the first time in history that series-produced tunnel elements of this size have been used to build a tunnel. The standard elements are enormous, hollow concrete structures which are 217 metres long and weigh more than 73,500 tonnes. The elements are divided into five tubes – two for the future motorway, two for the railway and one for technical installations.
“We are both happy and relieved. Our technology, our equipment and our contractors have demonstrated their capabilities and achieved something no one has done before. It is a very big day for the project, for Denmark and Germany and for Europe,” says Mikkel Hemmingsen, CEO of Sund & Bælt.
In the coming years, the remaining 88 elements will be immersed one by one and connected in an excavated trench in the seabed up to 40 metres below the sea surface. At 18 kilometres, the Fehmarnbelt tunnel will by far be the longest immersed tunnel in the world.
The Fehmarnbelt Fixed Link is an important part of Europe’s future transport network, which is intended to strengthen trade, mobility and security in Europe. The Fehmarnbelt tunnel has been designated a priority project by the European Commission, which has awarded the project roughly 1.3 billion Euro in construction funding.
“The immersion of the first tunnel element is a historic achievement. The world is watching, and you are showcasing European engineering and construction at its very best. The tunnel will connect regions more closely and create new momentum between Malmö, Copenhagen, Hamburg and onwards into Europe. The European Commission will continue to support this project all the way,” says Apostolos Tzitzikostas, the European Commissioner for Sustainable Transport and Tourism.
When the tunnel is completed, it will be possible to cross the Fehmarnbelt in 10 minutes by car and 7 minutes by train. The tunnel will also enable fast railway connections between Copenhagen and Hamburg in just 2.5 hours – a clear improvement on the current 5 hours.
Find videos and images from the operation here: Media kit First Immersion
The material is updated continuously.
