Jarlsberg Tunnel

Jarlsberg Tunnel

The northern entrance during the late phase of construction, before overhead wire was installed
Overview
Line	Vestfold Line
Location	Frodeåsen, Tønsberg, Norway
Coordinates	59°17′03″N 10°24′22″E / 59.2841°N 10.4061°E / 59.2841; 10.4061Coordinates: 59°17′03″N 10°24′22″E / 59.2841°N 10.4061°E / 59.2841; 10.4061
Start	Tomsbakken
End	Frodegata
Operation
Opened	7 November 2011
Owner	Norwegian National Rail Administration
Technical
Line length	1,750 m (5,740 ft)
No. of tracks	Double
Track gauge	1,435 mm (4 ft 8 1⁄2 in)
Electrified	15 kV  16 2⁄3 Hz AC
Operating speed	200 km/h (120 mph)

The Jarlsberg Tunnel (Norwegian: Jarlsbergtunnelen) is a 1,750-meter (5,740 ft) long double track railway tunnel which runs through Frodeåsen in Tønsberg, Norway. Located on the Vestfold Line, the tunnel was built as part of the 7.8-kilometer (4.8 mi) double-track high-speed segment from Barkåker to Tønsberg. It is located just north of Tønsberg Station and runs between Frodegata and Tomsbakken. Most of the tunnel is blasted, although 223 meters (732 ft) is in a concrete culvert. Planning of the tunnel started in the late 1990s. Several railway interest groups advised against building the isolated segment of upgraded track without a complete plan for upgrading the entire line. Construction started in April 2009 and the new section and the tunnel opened on 7 November 2011. It was the fourth segment of the Vestfold Line to be upgraded.

The Jarlsberg Tunnel runs roughly north–south through Frodeåsen, a hill just north of the town center of Tønsberg. The northern entrance is located at Tomsbakken, beside County Road 35 and the southern entrance is located at Frodegata in the town center. Just south of the tunnel lies Tønsberg Station. The tunnel is 1,750 meters (5,740 ft) long, of which 1,560 meters (5,120 ft) is blasted through bedrock and 223 meters (732 ft) is concrete culvert. The portal on the Tønsberg side is 73 meters (240 ft) long.

The Jarlsberg Tunnel constitutes the southernmost part of the 7.8-kilometer-long (4.8 mi) double-track segment of the Vestfold Line between Barkåker and Tønsberg. It is electrified at 15 kV  16 ²⁄₃ Hz AC, has an NSI-63 signaling system and is dimensioned for 200 kilometers per hour (120 mph). The crosscut serves as an emergency exit. The railway tunnel crosses 2.5 to 3.0 meters (8 ft 2 in to 9 ft 10 in) above the Frodeåsen Tunnel, a twin-tube tunnel of County Road 300. The tunnel's single crosscut serves as an emergency exit. The line is owned and maintained by the Norwegian National Rail Administration.