In December 2016, diesel bus line 20 will be converted to trolleybus line 9 with a new route in the East of Salzburg. Fleet Former fleet Until recently, almost all of the trolleybuses operating on the Salzburg system were made either by the German company MAN or its Austrian counterpart Gräf & Stift. After the former company took over the latter in 1971, the Gräf & Stift name remained in use as an MAN brand for the Austrian market and for trolleybuses until 2001, when ÖAF-Gräf & Stift AG was renamed MAN Sonderfahrzeuge AG. With the retirement of large numbers of Gräf & Stift vehicles since the start of the 21st century, the MAN/Gräf & Stift portion of the fleet has been now much reduced. Some of the retired Salzburg vehicles were sold to other trolleybus operators. By that means, former Salzburg trolleybuses later entered service on the since-closed trolleybus system in Kapfenberg, Austria, and also in Germany (Eberswalde), Lithuania (Vilnius), Romania (Mediaş and Timișoara) and Russia (Perm and Rybinsk). Until 1975, trolleybuses also operated with trailers. Salzburg was the last trolleybus network in Austria in which this form of operation was to be found. There were four different models of trailer available. They were made by Gräf & Stift (type OA I), Kässbohrer (without model designation), Lohner (type OM 5/1) and Schumann (without model designation). Table of former fleet Current fleet The oldest vehicles in the current fleet are the 23 high-floor Gräf & Stift articulated trolleybuses built between 1988 and 1994. With three exceptions, they are powered by an induction motor. This series originally consisted of 36 vehicles, of which 35 were built for Salzburg. The other one, fleet no. 220, was bought secondhand from the Kapfenberg trolleybus system. The first low-floor trolleybuses to be added to the system were the 23 MAN articulated vehicles constructed between 1994 and 1997. One of them, fleet no. 240, is likewise a used vehicle from Kapfenberg. The Van Hool vehicle generation, in the fleet since 2000, similarly offers only low-floor entrances. Of the 32 Van Hool vehicles, 13 were equipped with a diesel-powered auxiliary drive, the first such devices to be fitted to vehicles in the Salzburg fleet. On 24 November 2008, two more Van Hool articulated vehicles arrived in Salzburg as secondhand acquisitions from the Vevey–Villeneuve trolleybus system, in Switzerland. These had been Vevey–Villeneuve fleet nos. 2 and 15, built