Map of the the Balkan Front — Germany's Southeast Front — with the mountain passes between Austria-Hungary and Romania. From the Reichsarchiv history of the wars in Serbia and Romania, Herbstschlacht in Macedonien; Cernabogen 1916.
The capitals of Belgrade (Serbia), Bucharest (Romania), Sofia (Bulgaria), and Constantinople (Turkey) are prominent, as is Salonica, Greece, the Allied entry port into the country.