Roslagsbanan

Roslagsbanan (lit. 'the Roslagen Line') is a narrow-gauge commuter railway system in Roslagen, Stockholm County, Sweden. Its combined route length is 65 kilometres (40 miles) and there are 38 stations. It is built to the Swedish three foot (891 mm or 2 ft 11+3⁄32 in) gauge. The Storstockholms Lokaltrafik (SL) classifies it as "light rail" in its maps.

The line starts in Stockholm at Stockholm Östra station. It goes north and splits into three branch lines at the junction stations Djursholms Ösby and Roslags Näsby; the three branches terminate at Näsbypark, Österskär and Kårsta.

It is double track between Stockholm and Viggbyholm and between Rydbo and Åkersberga. The rest is single track, but the line to Vallentuna was being doubled in 2012 and Rydbo-Åkers Runö in 2013. There are passing loops at some stations on the single track sections: at Altorp, Hägernäs, Österskär, Visinge, Täby kyrkby, Ormsta, Lindholmen and Kårsta.

Following a 2017 agreement between the Swedish state, Stockholm County, and the affected municipalities, the line will be extended to the centrally located underground hub T-Centralen, with construction to begin in approximately 2022.