Since 1868 a horse tramway ran on schedule from the Lánchíd to Zugliget [hu] set in operation by the Budai Közúti Vaspálya Társaság (~ Public Railway Society of Buda).

The whole line was of standard gauge, built according to Riggenbach's cog-wheel system, and was operated by steam locomotives pushing coaches uphill and hauling them downhill.

The new owners soon started to upgrade the line, by electrifying it using the same 550/600V DC system used by the city's trams, by adding new passing loops, replacing old trackage, and providing better schedules.

The track was renewed using the Strub cog-wheel system, the line voltage was increased to 1,500V and new vehicles, built by SGP and BBC, introduced.

[5] The Urban and Suburban Transit Association (VEKE) is advocating that the line be extended in both directions (Normafa and Széll Kálmán tér).