These were Babylon, Ecbatana, and Persepolis, the capitals respectively of Chaldaea, Media, and Persia Proper, all great and ancient cities, accustomed to the presence of Courts, and all occupying positions sufficiently central to render them not ill-suited for the business of administration.

Next to these in order of dignity may be classed the satrapial residences, often the chief cities of old monarchies, such as Sardis, the capital city of Lydia, Dascyleium of Bithynia, Memphis of Egypt, Bactra of Bactria, and the like; while the third rank was held by the towns, where there was no Court, either royal or satrapial.
Before this chapter is concluded a few words must be said with respect to the countries which bordered upon the Persian Empire.

The Empire was surrounded, for the most part, either by seas or deserts.

The Mediterranean, the Egean, the Propontis, the Euxine, the Caspian, the Indian Ocean, the Persian Gulf, and the Arabian Gulf or Bed Sea washed its shores, bounding almost all its western, and much of its northern and southern sides; while the sands of the Sahara, the deserts of Arabia and Syria of India and Thibet, filled up the greater part of the intervening spaces.

The only countries of importance which can be viewed as in any sense neighbors of Persia are European and Asiatic Scythia, Hindustan, Arabia, Ethiopia, and Greece.
Where the Black Sea, curving round to the north, ceased to furnish to the Empire the advantage of a water barrier, a protection of almost equal strength was afforded to it by the mountain-chain of the Caucasus.
Excepting on the extreme east, where it slopes gently to the Caspian, this range is one of great elevation, possessing but few passes, and very difficult to traverse.