xv The Continental Area 301 



ancient rock plateau by a series of grand gorges, and, flow- 

 ing over the low plain, oozes into the North Sea along 

 several branches embanked above the sunk plain of Holland. 

 The Elbe drains the Bohemian plateau, and breaking 

 through the mountain barrier in " the Saxon Switzerland," 

 between the Erzgebirge and the Sudetic Range, winds 

 across the low plain north-westward to the North Sea. 

 The Oder and Vistula, from the northern slopes of the 

 Sudetic Range and Carpathians, flow northward to the 

 Baltic. The Danube is remarkable for its disregard of 

 mountain barriers. It rises on the eastern slope of the 

 Black Forest, flows eastward across the plateau north of 

 the Alps, and finds a way between the Alps and the 

 Bohemian Forest Range. After penetrating some smaller 

 ranges it turns south in several parallel channels across the 

 flat plain of Hungary, which plain was probably once a 

 great lake. It is joined by the Drave and Save from the 

 Alps, and the Theiss from the Carpathians, as it crosses 

 the nearly level plain. The narrow channel of the Iron 

 Gate, between the opposed ranges of the Carpathians and 

 Balkans, allows the Danube to enter the open plain, across 

 which it flows to a delta on the Black Sea. 



387. Rivers of Eastern Europe. The long southern 

 slope of Eastern Europe is traversed by the great rivers 

 Dnieper and Don, flowing through gorges cut in the low 

 plain to the Black Sea. The still greater Volga ( 89) rising 

 in the Valdai Hills winds eastward and southward, always 

 encroaching on its right bank, which is high and steep, and 

 always leaving successive alluvial terraces on its low left 

 bank. The Oka is the most important' of its many tribu- 

 taries on the right, and on the left the Kama, flowing from 

 the Ural Mountains, is the largest. When the Volga reaches 

 sea-level its course is directed south-westward, parallel to that 

 of the Don and very near that river, but the great stream 

 turns sharply south-eastward, splitting into numerous chan- 

 nels, and finally enters the closed Caspian Sea ( 335) by a 

 great delta. The short northern slope of Eastern Europe is 

 occupied by the basins of the Pechora flowing to the Arctic 

 Sea, and the Northern Dwina to the White Sea. 



