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World’s longest underwater tunnel is being built

World’s longest underwater tunnel is being built

Last Monday, King Frederik X of Denmark, who took office at the beginning of 2024, ceremoniously inaugurated the construction of the longest underwater tunnel of its kind. The tunnel, which will run between the Danish city of Rødby and the German village of Puttgarden, is a groundbreaking infrastructure project and will revolutionize current transport connections.

With an impressive length of 18 kilometers, the new immersed tunnel, which will run beneath the Fehmarn Belt, will reduce the current travel time of 45 minutes by almost 85 percent.

The tunnel, which will be tolled upon its planned completion in 2029, is a joint project between Denmark and Germany and is expected to cost EUR 4.8 billion. The financing and construction of the tunnel represents a significant investment in the region's future transport and economic infrastructure.

A total of four lanes are planned, which will allow drivers to cross the tunnel in around ten minutes. A separate route is planned for rail traffic, which will allow trains to travel through in just seven minutes. These optimisations will not only shorten travel times, but will also relieve traffic on the busy ferry routes and thus reduce environmental pollution.

To date, the Marmaray Tunnel under the Bosporus in Istanbul, Turkey, holds the record as the longest immersed underwater tunnel in the world. With the realization of the Fehmarnbelt Tunnel, Denmark will break this record and usher in a new era of transport infrastructure.

Construction of the tunnel is already well underway and is being carried out by an international consortium of engineers and construction companies. The technical challenges involved in building such a tunnel are enormous, but engineers are confident that the tunnel can be completed on time and within budget.


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