AGRICULTURAL SURVEY OF EUROPE. 
3 
extends from Pyret on the Austro-German frontier to Sulina on the 
Black Sea. Its chief ports are Vienna in Austria, Pressburg (Brati- 
slava) and Komorn in Czechoslovakia, Budapest in Hungary, Bel- 
grade in Yugoslavia, Rustchuk in Bulgaria, and Braila, Galatz, and 
Sulina in Rumania. These six countries with ports upon the 
Danube River are called the Danube States. 
The Danube has forced a passage called the "Iron Gate" between 
the ranges of the Transylvania Mountains in Rumania and the 
Mirotch Mountains (a continuation of the same general system) in 
Yugoslavia at Novo Orsova. At this point the current is very 
swift and a canal accommodating smaller boats has been constructed 
Fig. 1.— Map of the Danube States. 
around these rapids. The "Iron Gate'' thus divides the river 
traffic for large steamers into upper and lower Danube shipping. 
The general mountain ranges of the Carpathians, terminating at 
the north bank of the Danube, together with the Balkan Ranges 
beginning at the south bank of the Danube and stretching away 
south and east throughout the Balkan Peninsula, constitute an 
extended watershed that separates the Danube States into the Upper 
Danube Basin and the Lower Danube Basin. To a certain extent 
these mountain ranges differentiate the climate of the upper and 
lower basins. 
The Lower Danube Basin includes much of Rumania and northern 
Bulgaria. The Upper Danube Basin includes northern Yugoslavia, 
Hungary, Rumanian Transylvania, eastern Czechoslovakia and 
Austria. 
