Trolleybus transport was the last form of surface public transport to develop in Sofia, after
buses and
trams. The first Sofia trolleybus line opened on 8 February 1941, in what was then the
Kingdom of Bulgaria. It was more than long, and connected the city with the Gorna Banya quarter. The line was covered by 2
MAN trolleybuses, which were stored on the last stops during the night, due to the lack of depot. It closed on 9 September 1944. The city's second trolleybus system, the first part of the current system, opened on 1 May 1948, by which time the country had become the
People's Republic of Bulgaria. In the 1950s and 1960s, massive development of the trolleybus transport in Sofia began. At that time, the construction of new trolleybus routes proceeded especially rapidly, and two depots ("Stochna Gara" and "Nadezhda") were opened, with a total capacity of 160 trolleybuses. In 1951, the first Bulgarian made trolleybuses entered service. In 1987, a new depot, "Iskar", was opened with a capacity of 130 trolleybuses. Levski depot was opened in 1994 with capacity of 60 trolleybuses. As of 2021 three depots are in operation: Nadezhda, Iskar and Levski. The latter also serves as a storage and overhaul facility. ==Lines==