Citybanan

The Stockholm City Line (Swedish: Citybanan) is a commuter railway tunnel beneath central in Sweden which is used by the . The line is 6 kilometres (3.7 mi) long, double track and electrified. It has two stations: is located directly below T-Centralen, the central station of the . The Odenplan station is the other station, and it is located next to the Odenplan metro station. The line entered service on 10th of July 2017.

The tunnel significantly improves the traffic throughput to and from south of Stockholm as there are only two tracks in that direction from , the same number that were in place in 1871 when the railway was originally built. It has 24 scheduled trains per hour in each direction. The commuter trains pass Stockholm with up to 16 trains per hour per direction. The other eight are regional and long-distance trains. The tunnel takes all commuter trains, allowing more regional and intercity trains to operate along the old line.

Placing the commuter rail traffic into a tunnel of its own thus allows increased capacity for other national rail traffic through Central Station. The entire system for long-distance passenger railways in Sweden suffers from this bottleneck, since 80% of train rides in Sweden start or stop in Stockholm . As a result, there is no room to increase the frequency of commuter, regional, and long-distance trains despite their heavy usage.

Seen from south to north, the route of the Citybanan tunnel branches off the Connection Line after on Södermalm, and continues beneath the bay bottom of Riddarfjärden at Söderström, beneath the islet of Riddarholmen, beneath Riddarfjärden at Norrström, to the new City Station. From there, it continues beneath Norrmalm to Odenplan Station, then beneath to join with the East Coast Line at Tomteboda.

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Wikipedia