The Stockholm Metro, or Stockholms tunnelbana, is the metro system in Stockholm, Sweden. The system has three main lines and one hundred stations, 47 of which are subterranean and 53 are aboveground (surface and elevated) stations.
The first part of the metro was opened in 1950, when an underground light rail line opened in 1933 was converted to metro standard. This line ran south from Slussen station. Over the following years, this line was expanded to three lines going south from the inner city. In 1952 a line from the inner city to the western suburbs was opened. In 1957 the two line were connected via the central station and old town. This system consisting of three lines now forms the Green line. The Red line was opened in 1964 with two lines going from northeast to southwest. The final system, the Blue line, was opened in 1975 with two lines going northwest from the city center. The latest addition to the Green Line was carried out in 1994.
Stockholm's metro is well known for its decoration of the stations; it has been called the longest art exhibit in the world. Several of the stations (especially on the Blue line) are left with the bedrock exposed, crude and unfinished, or as part of the decorations. At the Rissne station, an informative wall fresque about the history of Earth's civilizations runs all along both sides of the platform.
The metro system is owned by the Stockholm County Council, which presently has contracted the operation to Connex. The Stockholm Metro was the site of distribution for the first edition of Metro, now a world-wide chain of free newspapers.