Alexander passed the next winter at the city of his own founding, Alexandreia, in the Koh Daman to the north of Kabul. And from thence in two divisions he started for the Indus, sending the main body of his troops by the most direct route, with Taxila (the capital of the Upper Punjab) for its objective, and himself with lighter brigades specially organized to subdue certain tribes on the northern flank of the route who certainly would imperil the security of his line of communication if left alone. This was his invariable custom, and it was greatly owing to the completeness with which these flanking expeditions were carried out that he was able to keep open his connection with Greece. There have been discussions as to the route which he followed. Hyphæstion, in command of the main body, undoubtedly followed the main route which would take him most directly to the plains of the Punjab, which route is sufficiently well indicated in these days as the "Khaibar." We hear very little about his march eastwards. [Illustration: SKETCH MAP OF ALEXANDER'S ROUTE] In the days preceding the use of fire-arms the march of a body of troops through defiles such as the Khurd Kabul or the Jagdallak was comparatively simple. So far from such defiles serving as traps wherein to catch an enemy unawares and destroy him from the cliffs and hills on either side, these same cliffs and hills served rather as a protection. The mere rolling down of stones would not do much mischief, even if they could be rolled down effectively, which is not usually the case; and in hand-to-hand encounters the tribespeople were no match for the armoured Greeks. Alexander's operations would preserve his force from molestation on its northern flank, and the rugged ridges and spread of desolate hill-slopes presented by the Safed Koh and other ranges on the south has never afforded suitable ground for the collection of fighting bodies of men in any great strength. General Stewart marched his force from Kabul to Peshawur in 1880 with his southern flank similarly unprotected with the same successful result, his movements being so timed as to give no opportunity for a gathering of the Ghilzai clans. On the northern flank of the Khaibar route, however, there had been large tribal settlements from the very beginning of things, and it was most important that these outliers should feel the weight of Alexander's mailed fist if the road between Kabul and the Indus were ever to be made secure. He accordingly directed his attention to a more northerly route to India which would bring him into contact with the Aspasians, Gauraians, and Assakenians.