By 2029, Denmark and Germany will be connected by an underwater tunnel.
When it is finished in 2029, the Fehmarnbelt Tunnel will be the longest combined rail and road tunnel ever built. The project spans the Fehmarn Belt, a section of the Baltic Sea.
One of the largest infrastructural projects in Europe, the tunnel will be 18 kilometres long. Its construction will cost more than 7 billion euros. In order to provide some context, consider that the 50-kilometer tunnel that united England and France in 1993 cost the equivalent of $13.6 million. The Channel Tunnel was created using a boring machine as opposed to engulfing pre-made tunnel sections, despite being longer than the Fehmarnbelt.
The tunnel will be constructed through the Fehmarn Belt, a strait that separates the Danish island of Lolland from the German island of Fehmarn. It's intended to replace the ferries that currently run between Rdby and Puttgarden and carry millions of people each year. While it would only take seven minutes by train and ten minutes by vehicle, the passage now requires 45 minutes to complete by boat.
Millions of people use a very crowded ferry service that will be replaced with a road link, cutting travel times by over an hour. Additionally, Denmark intends to construct high-speed electric rail lines to and from the tunnel. Additionally, rail service will continue to Sweden, Norway, and Finland after crossing the Danish border.