The tram network of Budapest is part of the mass transit system of Budapest, the capital city of Hungary. Tram lines serve as the second-most important backbone of the transit system after the bus network, carrying almost 100 million more passengers annually than the Budapest Metro.[4] In operation since 1866,[5] the Budapest tram network is among the world's largest tram networks by route length—operating on 174 kilometres (108 mi) of total route[3]—and is the busiest in the world.[6][7]
As of 2023[update], the tram network is made up of 35 regular lines (26 main lines and 9 supplemental lines) and the Budapest Cog-wheel Railway (signed as route 60).[1] The system is operated by Budapesti Közlekedési Zrt. under the supervision of the municipal Budapesti Közlekedési Központ. Since 2016, the system uses the world's longest 9-sectioned articulated tram vehicle, the CAF Urbos 3/9, on route 1.