Tyholt Tunnel

Tyholt Tunnel

The tunnel seen from Lerkendal
Overview
Line	Stavne–Leangen Line
Location	Trondheim, Norway
Coordinates	63°25′33″N 10°25′48″E / 63.42583°N 10.43000°E / 63.42583; 10.43000Coordinates: 63°25′33″N 10°25′48″E / 63.42583°N 10.43000°E / 63.42583; 10.43000
System	Norwegian railway
Start	Lerkendal
End	Lademoen
Operation
Opened	1 June 1957
Owner	Norwegian National Rail Administration
Operator	CargoNet, Cargolink
Character	Freight
Technical
Line length	2,785 m (9,137 ft)
No. of tracks	Single
Track gauge	1,435 mm (4 ft 8 1⁄2 in)
Electrified	No

The Tyholt Tunnel is a 2,785-meter (9,137 ft) railway tunnel which runs between Lerkendal and Lademoen on the Stavne–Leangen Line in Trondheim, Norway. The line takes it name for passing under the neighborhood of Tyholt and only sees regular freight traffic.

Construction began by the Wehrmacht during the German occupation of Norway from 1940 to 1945, but the project was never completed. The Norwegian State Railways (NSB) resumed the work in the 1950s. Part of the tunnel was built using cut-and-cover, part using a tunneling shield and most of it was blasted. It opened on 1 June 1957.

The Tyholt Tunnel is a 2,785-meter (9,137 ft) un-electrified, single track, standard gauge railway tunnel. It constitutes nearly half of the 5.8-kilometer (3.6 mi) Stavne–Leangen Line, which acts as a bypass around Trondheim. The tunnel is owned by the Norwegian National Rail Administration. From the south end, the first 70 meters (230 ft) is a culvert, the next 198 meters (650 ft) run through sediments and the final 2,517 meters (8,258 ft) are in bedrock.

During the German occupation of Norway as part of the Second World War, the Wehrmacht wanted a railway route past Trondheim which was guarded against sabotage. They decided that the best way to do this was to build a tunnel under the neighborhood of Tyholt. However, construction of the tunnel took much longer than expected, so instead the Wehrmach started laying railway tracks in the streets in Trondheim. However, neither of the two lines were completed by the time of German capitulation on 8 May 1945.