Most routes to Belgrade have been cut off for reasons unknown. Consequently Belgrade (and the fate of its people) is the subject of much gossip around western Europe. The only access in or out of Belgrade is via a Viennese Military Transport carrying mechanical soldiers of the Austro-Hungarian Empire
If they manage to sneak aboard the military train, Passepartout and Fogg arrive to find Belgrade completely deserted. During the night the travellers will meet Pavle, one of the few remaining survivors, who tells that after the Austro-Hungarian automatons arrived the people of Belgrade started disappearing. Passepartout may hand over the Zauberflöte he acquired, which Pavle will hand to his sister Ljubica to produce more and thus aid them in their struggle against the mechanical army. This will grant the "Turn The Tide of War" achievement on Steam.
South-East to Sofia aboard the Goods' Wagon (if Passepartout asked for Pavle's help).