Zi U-9
ZiU-9 (in Russian ЗиУ-9) is the Soviet (and later Russian) trolleybus vehicle. Other names and indexes for the same vehicle include ZiU-682 and HTI-682 (respectively ЗиУ-682 and ХТИ-682 in Russian letters). The ZiU acronym stands for Zavod imeni Uritskogo, which means plant named after Moisei Uritsky, the Russian revolutionary. Before 1996 this acronym was also a trademark of the vehicle manufacturer. It has been changed to Trolza. The ZiU-9 was put in mass production in 1971 and it is still assembled along with other more advanced trolleybus vehicles on the Trolza (former ZiU) factory. The total number of produced ZiU-9s exceeds 40,000 vehicles. This model is the most numerous trolleybus vehicle in the world.
Read more about Zi U-9: History and Development, Modifications, ZiU-9G / ZiU-682G / ЗиУ-9Г Modification (1992), Operators, Greek Donation