The first Fehmarnbelt tunnel element, 217 meters long and 42 meters wide, is being lowered onto the seabed off Rødbyhavn as the project begins installation of 89 tunnel segments for the Fehmarnbelt fixed link between Denmark and Germany.

The Fehmarn Belt Tunnel spans about 18 kilometers and will connect Fehmarn in Germany with Lolland in Denmark, aiming to shorten travel times between Hamburg and Copenhagen and replace existing ferry services.

This milestone marks the transition to the element-lowering phase near Rødbyhavn, moving toward crossing into German waters.

The operation is highly complex and unprecedented in scale, requiring multiple tugs and a specialized lowering vessel, with engineers stressing minimal margins for error and tight coordination with wind and sea conditions.

The project faces potential delays; in January, Sund & Bælt warned that opening could slip to around 2031 due to missing permits, with a revised timetable to be issued once the first elements are sunk.

The first element weighs about 73,500 tons and is ballasted with an additional 4,500 tons of ballast concrete; it was transported from the Lolland factory harbor and lowering is expected to take 18 to 24 hours depending on currents and weather.

Delays on the German side are compounded by the need for a 1.7-kilometer undersea Fehmarsund crossing, with Deutsche Bahn planning a production facility in Großenbrode to support the timetable.

Each standard tunnel element measures 217 meters long and 42 meters wide, comprising four bores for road and rail, plus a narrow service duct between the highway bores.

The four-bore design houses both road and rail traffic, with a separate service duct for technical installations.

Five tugboats and a specialized lowering vessel are guiding and placing the element onto the seabed, with ballast water and concrete stabilizing the lift two kilometers offshore.

The lowering operation relies on a dedicated vessel and tugs to correctly position the segment as part of the undersea tunnel network.

Sund & Bælt emphasizes the Fehmarnbelt tunnel comprises four tubes for road and rail, noting the overall lowering process could span several days.