Romerike Tunnel

The Romerike Tunnel is a 14.580-kilometre railway tunnel in Norway between Oslo and Lillestrøm. It is the longest railway tunnel in Norway and forms the first section of the Gardermoen Line. It is double track and electrified, permitting speeds of 210 kilometres per hour .

Construction started in 1994, with plans to open with the rest of the Gardermoen Line and Oslo Airport, Gardermoen on 8 October 1998. Due to serious leakage from Lutvann and several other lakes, it did not open until 22 August 1999. The leaks increased the cost of the tunnel from 0.5 billion kr to NOK 1.8 billion. The main contractor was Scandinavian Rock Group. The tunnel was originally owned by NSB Gardermobanen, then the Norwegian National Rail Administration, and now owned by Bane NOR. The tunnel allows long-distance, regional and Flytoget Airport Express Trains to bypass the old Hoved Line, reducing journey times between Oslo and Lillestrøm from 29 to 12 minutes.

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