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 Bane NOR. The line opened as a narrow gauge railway, and rebuilt to standard gauge between 1913 and 1922. The line was electrified in 1922, as the first line on the national network to be electrified. The Lieråsen Tunnel shortened the line in 1973, and in 1980 the Oslo Tunnel was built, allowing the line to connect to the new Oslo Central Station. The Asker Line runs parallel to the Drammen Line, mostly in tunnels. At Drammen, the Vestfold Line branches off to the south while the Bergen Line and the Sørlandet Line continue together to Hokksund along the Randsfjorden Line. The entire line has double track due to the heavy traffic on the line. The longest Norwegian railway bridge is just before Drammen where the line crosses the Drammen river. That bridge is 454 metres long. History Both Drammen and Oslo were important ports serving Eastern Norway, and both had by the 1870s their own railway lines. Oslo was connected to Romerike by the Hoved Line and to Sweden by the Kongsvinger Line, while Drammen was connected to Ringerike by the Randsfjorden Line. The most important use of the lines were shipment of lumber to the respective ports for export, but the lines also saw an increasing passenger traffic. Due to the cheap and quick construction method propagated by NSB at the time, the Randsfjord Line was built in narrow gauge; the lines connecting to Oslo were on the other hand built in standard gauge, to ensure compatibility with the Swedish railway network. There was a considerable feeling of rivalry between the two cities at the time, and particularly in Drammen there was skepticism of building a line that could dilute the cities regional influence on behalf of the capital. Radical forces eventually succeeded in changing the tide of opinion, and Drammen politicians allowed the construction of the line. The rail gauge issue still created a problem, as did the location of the railway station in Oslo; Oslo East Station was located at the then east end of the city, and a line from Drammen—located to the west of Oslo—would either have to take the long trip around the north of the city, or terminate at