Tvärbanan (lit. 'the Transverse Line') is a light-rail line in Stockholm, Sweden, which runs largely in a semicircle south, west and north around central Stockholm - crosswise to the otherwise radial metro and commuter rail lines of Stockholm. It links together several transit lines through its connections with the southern, western and northern metro branches of the Stockholm Metro (Tunnelbana) as well as three branches of the Stockholm commuter rail (Pendeltåg).
https://en.wikipedia.org/wiki/Tv%C3%A4rbanan