Antiochus traversed the worst part of the road in the manner I have described, safely but very slowly and with difficulty, only just reaching the pass of Mount Labus on the eighth day.
The barbarians were collected there, convinced that they would prevent the enemy from crossing, and a fierce struggle now took place, in which the barbarians were forced back for the following reason.
Formed in a dense mass they fought desperately against the phalanx face to face, but while it was still night the light-armed troops had made a wide detour and occupied the heights in their rear, and the barbarians, the moment they noticed this, were panic-stricken and took to flight.
The king made every effort to restrain his men from continuing the pursuit, summoning them back by bugle-call, as he wanted his army to descend into <a class="linkToPlace" target="_blank" href="/place?placename=Hyrcania&groupId=640&placeId=1172">Hyrcania</a> unbroken and in good order.
Having regulated his march in the manner he wished he reached Tambrax, an unwalled city, but of large size and continuing a large royal palace, and encamped there.
Most of the enemy, both from the scene of the battle and from the surrounding country, had retreated to a town called <a class="linkToPlace" target="_blank" href="/place?placename=Sirynx&groupId=980&placeId=1732">Sirynx</a>, which was at no great distance from Tambrax, and was as it were the capital of <a class="linkToPlace" target="_blank" href="/place?placename=Hyrcania&groupId=640&placeId=1172">Hyrcania</a> owing to its strength and favourable situation, and he decided to take this city by storm.
He advanced therefore with his army and encamping round it began the siege.
The chief means he employed was the use of mantelets for sappers. There were three moats, each not less than thirty cubits broad and fifteen deep, and each defended at its edge by a double row of palisades, and behind all there was strong wall.
There were constant combats at the works, in which neither side could bring off their dead and wounded, as the hand-to-hand fighting took place not only on the surface of the ground but beneath it in the mines.
But in spite of all, owing to the superiority of numbers and the personal activity of the king, the moats were very soon filled up and the wall was undermined and fell,
upon which the barbarians were thoroughly discouraged, and after killing all the Greeks in the town and pillaging all the finest things they made off by night.
When the king became aware of this he sent Hyperbas after them with the mercenaries, and the barbarians when overtaken by him threw away their encumbrances and fled again into the town.
When the peltasts now vigorously forced their way through the breach, they surrendered in despair.
Walbank Commentary