GSP Belgrade () is a public transit company in the city of Belgrade. As of 2018, it operates with 170 lines and has 1,611 active vehicles. Name The acronym "GSP" stands for Gradsko saobraćajno preduzeće (). History Its history dates back to 14 October 1892 when the first horse tram line began operating in Belgrade between Slavija and Terazije. It was known under the name Beogradska varoška železnica (). The first bus line was opened in 1925 and in 1947 the first trolleybuses appeared in Belgrade. 1940–1990 In 1940, the tram traffic took place on 10 lines. Belgrade has disposed of 104 trams, 60 trailers and 87 buses. The following year, in the bombing of Belgrade was destroyed 38 trams, 36 trailers and 10 buses. In 1945, company changed its name to the Department of traffic lights and the Executive Committee of the City of Belgrade. In Belgrade Radio 4 tram and bus lines 3 with a total of 58 vehicles. In 1947, the first trolley was introduced to the line Kalemegdan – Slavija. In 1955, in Belgrade was 8 tram lines with 162 trams, three trolley lines with 42 trolley buses and 14 bus routes with 148 buses. In 1956, he was released into operation first trolleybus domestic production - "Goša FOM". Belgrade and Zemun are associated trolley lines. As of 1960, there was 38 lines (7 tram, 6 trolleybus and 14 bus). Number of vehicles in inventory stood at 467. In 1961, 160 Leyland buses were purchased. In 1962, cab vehicles were introduced, a total of 63 vehicles. In 1970, 144 new vehicles were purchased for the transport of Belgrade. The total number of vehicles has increased to 806. In 1975, new zonal tariff system was introduced and number of vehicles rose to 995. By 1985, the total number of vehicles was 1380, and the average number of vehicles in traffic in operation was, on weekdays was 779. In 1989, an integrated system of unified tariff system, in addition to Lasta and GSP in the system is turned on and ZTP Beograd and ATP Pancevo. 1990–2000 By the decision of the Assembly of Belgrade, GSP "Belgrade" in 1990 became a public utility company, founded by the city. In 1991, with a total of 1,393 vehicles, with average age of 4.5 years, the streets of Belgrade was at the peak was about 1,130 vehicles a day carrying about 2.5