32- POLSKA
from the sea, and to shut it into its landlocked heart. The Pomeranian Lakeland,
the Mazurian Lakeland, and the Lithuanian Lakeland form belts of sparsely
inhabited terrain which interrupt free movement and inhibit settlement. It is
interesting to note how the northern frontier of Poland was mainly held on the
margin of these lakes from the earliest times to the twentieth century. (See
Diagram B.)
In contrast, the river system of Poland emphasizes the longitudinal axis. The
basins of the Odra and Vistula both drain from the Carpathians to the Baltic. In
Byelorussia, the Berezina, the Upper Dnieper, and the Soz all cut across the over-
land passageways, just as in Red Ruthenia or Podolia, the numerous tributaries
of the Dniester constantly interrupt the sweep of the Podolian plateau. The
emergence of the Odra and Vistula from their sources by the Moravian Gate, the
one point between the Black Sea and Bavaria where southern Europe can be
approached without crossing an alpine pass, underlines the longitudinal axis
Diagram B. Poland - Physical Structure