The areal extent and diversity of the natural landscapes of Inner Asia impel a survey of the geographic background of this region to concentrate on the environmental characteristics which seem to contribute most to an understanding of the even greater complexities of the human use of these lands. To this end, attention will be focused initially on five general geographic features of Inner Asia: its size; the effects of distance from maritime influences on movement and climate; the problems of its rivers; geographic diversity and uniformity; and, the limited capabilities for areally extensive crop agriculture. This will be followed by a discussion of the major environmental components of the natural zones of Inner Asia.

General geographic characteristics

The Inner Asian region occupies an immense area in the interior and northerly reaches of the Eurasian land mass and encompasses a territory of more than eight million square miles or about one-seventh of the land area of the world. The east–west dimensions of this region extend some 6,000 miles, which is slightly more than twice as long as the maximum north–south axis. These distances are comparable to those traversed by only a few of the most adventurous maritime vessels in the European “Age of Discovery.” Within Inner Asia, however, the pre-eminent means of long-distance communication has been overland movement inasmuch as no region on earth is as landlocked by the absence of feasible maritime alternatives. The major movements of peoples, cultural innovations, and goods has been on Inner Asian land routes far removed from the Pacific, the ice-covered Arctic and the Indian Ocean.