An arrow-shaped viewpoint lets the public watch a tunnel take shape

Engineering firm Arup has designed a viewpoint shaped like an arrow, so the public can watch the Fehmarnbelt Tunnel being built. Dezeen reported the design on 25 October 2026.

The structure is called Pilen, which is Danish for "the arrow." Its point faces the spot in Germany where the tunnel comes up out of the ground. It stands beside the construction site at Rødbyhavn, on the Danish side of the Baltic Sea.

Pilen was designed for Femern, the contractor overseeing the tunnel work. The walkway is 217 metres long, and that length matches the length of each of the 89 concrete sections that will make up the tunnel. The walkway rises 24 metres above sea level.

The viewpoint is built from landfill timber and steel. It is meant to be taken apart once the tunnel is finished, so it does not stay on the coast after the job ends.

The tunnel itself is an 18-kilometre road and rail link. It runs underwater between Rødbyhavn in Denmark and Puttgarden in Germany. Its completion is scheduled for 2029.

In May 2026, the first tunnel section was lowered into place. New Civil Engineer reported that the element was immersed on the Danish side. Arup has said that, once complete, the Fehmarnbelt Tunnel will be the longest immersed tunnel in the world. An immersed tunnel is built in sections on land, floated out, and sunk into a trench on the seabed.

For anyone who has wondered what happens behind the fences of a large construction job, the new viewpoint gives a clear sight line. Most of the work below the waterline stays out of view, but the arrow points straight at where the story ends.