The SL C5, colloquially the Silver Arrow, was a type of subway train used in the Stockholm metro, Sweden. It was a prototype train produced in one example of 8 cars and was never painted, instead keeping its aluminium "silver" finish. It was rare in trafic and often ran during the night, giving it a mystic appearance, resulting in several urban legends alleging sightings of a silver colored ghost train, simply known as the Silver train, but also "the Silver Arrow".

The Stockholm Metro is a rapid transit system in Stockholm, Sweden. The first line opened in 1950 as the first metro line in the Nordic countries, and today the system has 100 stations in use, of which 47 are underground and 53 above ground. There are three coloured lines, as shown on the tube maps, which form seven numbered routes with different termini. Routes numbered 17, 18 and 19, 13 and 14 and 10 and 11 all go through the centre of the city, resulting in a very centralized system. All three lines and seven routes interchange at T-Centralen station. Apart from this, there are three other interchange between lines, at Fridhemsplan, Slussen and Gamla stan stations.