After this, Alexander despatched Parmenio with the baggage, the Thessalian cavalry, the Grecian allies, the mercenary auxiliaries, and the rest of the more heavily armed soldiers, to march into Persis along the carriage road leading into that country. He himself took the Macedonian infantry, the Companion cavalry, the light cavalry used for skirmishing, the Agrianians, and the archers, and made a forced march through the mountains. But when he arrived at the Persian Gates, he found that Ariobarzanes, the viceroy of Persis, with 40,000 infantry and 700 cavalry, had built a wall across the pass, and had pitched his camp there near the wall to block Alexander’s passage. Then indeed he pitched his camp there; but next day he marshalled his army, and led it up to the wall. When it was evident that it would be difficult to capture it on account of the rugged nature of the ground, and as many of his men were being wounded, the enemy assailing them with missiles from engines of war placed upon higher ground, which gave them an advantage over their assailants, he retreated to his camp. He was informed by the prisoners that they could lead him round by another route, so that he might get to the other end of the pass; but when he ascertained that this road was rough and narrow, he left Craterus there at the camp with his own brigade and that of Meleager, as well as a few archers and 500 cavalry, with orders that when he perceived he had got right round and was approaching the camp of the Persians (which he could easily perceive, because the trumpets would give him the signal), he should then assault the wall. Alexander advanced by night, and travelling about 100 stades, he took the shield-bearing guards, the brigade of Perdiccas, the lightest armed of the archers, the Agrianians, the royal squadron of cavalry Companions, and one regiment of cavalry besides these, containing four companies; and wheeling round with these troops, he marched towards the pass in the direction the prisoners led him. He ordered Amyntas, Philotas, and Coenus to lead the rest of the army towards the plain, and to make a bridge over the river[447] which one must cross to go into Persis. He himself went by a route difficult and rough, along which he nevertheless marched for the most part at full speed. Falling upon the first guard of the barbarians before daylight,[448] he destroyed them, and so he did most of the second; but the majority of the third guard escaped, not indeed by fleeing into the camp of Ariobarzanes, but into the mountains as they were, being seized with a sudden panic. Consequently He fell upon the enemy’s camp at the approach of dawn without being observed. At the very time he began to assault the trench, the trumpets gave the signal to Craterus, who at once attacked the advanced fortification. The enemy then, being in a state of confusion from being attacked on all sides, fled without coming to close conflict; but they were hemmed in on all