Now as then the roadways follow the lines of least resistance. But, owing to the peculiar topographical conditions of many parts of the Near East, the traveler’s choice of direction is necessarily limited. In the broad and inhospitable desert his course will necessarily depend on the location of the few existing springs and wells and wadis, while in the mountainous regions it will, in great measure, be governed by a few and widely-separated passes. In many cases, too, where broad and deep rivers are to be crossed, the direction taken, especially during the season of rains and floods, will vary with the condition of often-changing and frequently treacherous fords. The celebrated Royal Road, of which Herodotus gives so graphic an account, is a case in point. The student of ancient history is surprised when he first observes its circuitous course between the one-time capital of Persia and the famous emporium of Crœsus, but the reason of it becomes evident when he learns something of the character of the country through which it passed. He then discovers that the prehistoric travelers--long centuries before the days of Cyrus and Darius and Xerxes--who first selected this long and roundabout route between the plains of Mesopotamia and the shore of the Ægean--a route which took them over high mountains and pitiless deserts and dangerous morasses--did simply what a modern railroad engineer would do under similar circumstances--chose for their venturesome journey the line of least resistance.[263] It must, however, here be observed that the word “road,” as used in the Orient, rarely has the same meaning which we attach to the term. There a road is rarely anything more than the line of route marked by the footprints of travelers or beasts of burden. Even the Royal Highway between Susa and Sardis was nothing more than this. It was only when the Romans--the great road builders of antiquity--became masters of western Asia that its leading cities were connected by roads in our conception of the word. Now, however, only traces of these splendid highways constructed by the Cæsars exist, and roads available for wheeled vehicles are still almost as rare in most parts of the Near East as they were in the time of Tigranes or Tiglath-Pileser. But, although the great majority of eastern roads have never felt a spade or pick-ax, and are nothing more than evanescent footprints in spongy swamp or shifting sand, nevertheless there hangs over most of them an air of legend and romance and historic association which stimulates the mind of the traveler in a preëminent degree and affords as much food for thought as he can find in any of the great highways of the more civilized regions of the modern world.