Tromsøysund Tunnel

The Tromsøysundtunnel is an undersea road tunnel road number 8 in the Norwegian city of Tromsø in Troms Fylke. The tunnel leads under the Tromsøysund and connects the boroughs of Tomasjorda on the mainland and on the island Breivika Tromsøya. The tunnel has two parallel tubes, of which the T1 tube 3386 meters and the T2 tube are 3500 meters long. At the lowest point of the tunnel is 102 meters below sea level. The largest slope is 8.2 %. In 1994, the tunnel was opened to relieve traffic congestion on the Tromsøysundbrücke.

The Tromsøysundtunnel was the first and for 16 years the only undersea tunnel with two tunnels in Norway before the squire tunnels were opened in Bergen and the Bjørvikatunnel in Oslo in 2010. The Tromsøysundtunnel has 15 cross- links between the two tubes. For pedestrians it is authorized.

In 2010 the tunnel was illuminated speed indicators, as deposit on the signs much exhaust and make it so difficult to read. Two years later, automatic flash boxes were added.