Fehmarnbelt Tunnel which is going to connect Denmark and Germany will be the longest underwater tunnel in the world after completion. The countries decided to go on with the ambitious project in 2010. Although it took 10 years for the construction to start, the project is in progress and developing quickly. The officials expect the tunnel to be finished in 2029 and cost around 9 billion dollars.

The name of the longest underwater tunnel comes from the German island of Fehmarn to which the one end of the road will lead.

The road will directly link the Danish island of Lolland to Fehmarn and shorten the travel time greatly. For example, today, the only form of transportation between the islands is obviously by sea, especially ferries. However, these ferry rides cost a lot and take 45 minutes. Moreover, people spend time for boarding and departing the ferry as well which makes the journey even more tiresome and longer.
The Fehmarnbelt Tunnel will lower the traveling time at least by 30-35 minutes. So, the road between the islands will only take 10 minutes by car.

In addition to its title as the longest underwater tunnel, with its 18-kilometer length, the Fehmarnbelt Tunnel will be the longest rail tunnel as well. One of the most peculiar aspects of this daring project is that the idea behind it is not new or unique at all. Since the 19th century, there have been talks of connecting Denmark and Germany in some way between the two countries.

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