Lieråsen Tunnel is a railway tunnel

Tunnel

A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...

 on Drammenbanen

Drammenbanen

The Drammen Line is a railway line between Oslo and Drammen, Norway, which was opened on 7 October 1872. It serves all trains west of Oslo Central Station and is owned by the Norwegian National Rail Administration....

 between Asker Station

Asker Station

Asker is a railway station located in downtown Asker in Akershus, Norway. The station serves as the main public transportation hub for the municipalities located around the Asker Line, the Drammen Line and the Spikkestad Line. The station was opened with the Drammen Line in 1872...

 and Lier Station

Lier Station

Lier Station is a railway station located at the village of Lier, Norway on the railway Drammen Line. The station is served by commuter trains 440 and 450 with half hour headway by Norges Statsbaner.-History:...

 in Norway

Norway

Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...

. The 10,723 m long tunnel was opened in 1973 and was the longest railway tunnel in the country until Romeriksporten

Romeriksporten

The Romerike Tunnel is a railway tunnel in Norway that connects Oslo with Lillestrøm. Being the longest railway tunnel in Norway, the tunnel forms the first half of the Gardermoen Line...

 was opened in 1999.

After the tunnel was opened, the railway line between Asker and Spikkestad Station

Spikkestad Station

Spikkestad Station is a railway station located at Spikkestad in Røyken, Norway and the terminus of Spikkestadbanen. The station was opened as part of Drammenbanen in 1885, but in 1973 the new Lieråsen Tunnel opened through Lieråsen, and the old part of Drammenbanen was transformed to a commuter...

 was kept for commuter trains, though the traffic between Spikkestad and Drammen Station

Drammen Station

Drammen is a railway station located in downtown Drammen in Buskerud, Norway. The station is the terminus of both the Randsfjord Line, the Drammen Line and the Vestfold Line...

was terminated.