The Government of Norway is planning to construct a submerged-floating road tunnel that will carry traffic though one of the country’s deepest fjords.

The tunnel is part of a project known as Ferry-free E39 that aims to cut the travel time in half. The E39 highway is around 700 miles long and connects Trondheim in the north to Kristiansand in the south.

Ferry-free E39 is expected to cost $40bn and includes construction of a number of bridges over the fjords, along with a 27km-long, 400m-deep rock tunnel.

Suspended approximately 100ft under the water’s surface, the floating tunnel will comprise two tubes. One will be for incoming traffic and the other will be for outgoing vehicles.

According to the Norwegian Public Roads Administration, the tubes will be affixed to floating pontoons and be separated by a gap of approximately 800ft.

“By 2035, we should have cut that to 11 hours by replacing the ferries with fixed crossings.”

The submerged-floating road tunnel will allow ships to sail over, while submarines can also pass freely underneath the tunnel.

Norway Public Roads Administration programme manager Kjersti Kvalheim Dunham told The Telegraph: “It’s nearly 1,100km from end to end, but the journey takes 21 hours on a good day, because of the seven ferry crossings en route.

“By 2035, we should have cut that to 11 hours by replacing the ferries with fixed crossings.”

In addition to the submerged tunnel, the government is planning to construct a 17 mile-long tunnel under a 1,000ft-deep fjord.

The Ferry-free E39 project is scheduled to be completed by 2050.