Figure 4. Topography and Drainage
Stretching in a broad arc across western Bolivia, the Andes define the country's three geographic zones: the mountains and Altiplano in the west, the semitropical Yungas and temperate valleys of the eastern mountain slopes, and the tropical lowlands or plains (llanos) of the eastern lowlands, or Oriente. The Andes run in two great parallel ranges or cordilleras. The western range (Cordillera Occidental) runs along the Peruvian and Chilean borders. The eastern range (Cordillera Oriental) is a broad and towering system of mountains stretching from Peru to Argentina. Between the two ranges lies the Altiplano, a lofty plateau 805 kilometers long and 129 kilometers wide (see fig. 4).
Data as of December 1989