Portal:Trains/Selected article/Week 18, 2012

The Jarlsberg Tunnel (Jarlsbergtunnelen) is a 1750 m 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 km 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 m 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.