BG Voz

BG Voz (Serbian Cyrillic: БГ Воз; stylized as BG:VOZ) is a commuter rail system that serves the city of Belgrade, Serbia. Operated by the "Beogradski metro i voz" public utility company, the system connects the central parts of Belgrade to its distant suburbs via four primary lines. Urban trains carry passengers between the termini of Ovča, Batajnica and Resnik, while suburban ones reach towards Mladenovac and Lazarevac in the south. The system runs on the same infrastructure as the national Serbian Railways and is directly linked to regional and intercity trains. Additionally, BG Voz provides transfers to the city's ground transport.

The system serves 35 stations, the majority of which are either elevated (ex. New Belgrade) or at-grade (ex. Ovča). There are only two underground stations, both in the central part of Belgrade: Karađorđe's Park and Vukov spomenik. They are linked to each other and the following stations by the Vračar and Dedinje Tunnels passing under the city. Two of the major lines - 1 and 3 - meet at Belgrade Centre station, while the other two - 2 and 4 - go through Karađorđe's Park. Additionally, Belgrade Centre is served by supplementary Zemun-bound lines.

Used by thousands of people every day, BG Voz has been described as the fastest transportation mode in Belgrade, but also the least maintained. Common issues include the trains' age, irregular departures, overcrowding and poor hygienic conditions. Plans exist both to introduce new trains and construct additional lines, which are aimed to connect Makiš to Karaburma and Zemun Polje to the future National Stadium.