Titus Livius (Livy), The History of Rome, Book 36
Evan T. Sage, PhD professor of latin and head of the department of classics in the University of Pittsburgh, Ed.

16. With a spirit wholly unlike theirs at that time, Antiochus pitched his camp within the “Gates” to the place and besides blocked the pass with fortifications, and when he had strengthened everything with [2??] a double wall and ditch and, where the situation demanded, with a rampart constructed out of the great [3??] quantity of stones which were scattered all about, confident that the Roman army would never force a passage, of the four thousand Aetolians —for so many had assembled —he [4] sent part to hold Heraclea with a garrison, part to Hypata,¹ being both certain that the consul would attack [p. 207]Heraclea and informed by many messengers that all² the country around Hypata was being devastated. [5] The consul, having first ravaged the fields of Hypata and then of Heraclea, the aid of the Aetolians being useless to both, encamped within the pass itself near the springs of hot water facing the king. Both contingents of Aetolians shut themselves up in Heraclea. [6] Antiochus, to whom, before he saw the enemy, everything seemed well fortified and guarded by posts, was terror-stricken lest the Roman should find trails somewhere over the overhanging cliffs to permit their passage; [7] for the story was that so the Lacedaemonians were once surrounded by the Persians, and recently Philip³ by the Romans themselves; [8] so he sent a runner to the Aetolians in Heraclea that they should render at least so much service to him in this war as to seize and hold the mountain-tops round about, that the Romans might find no way to cross. [9] On hearing this message a disagreement arose among the Aetolians. Part thought that they should obey the king's order and go, part that they should wait at Heraclea [10??] for either turn of fortune, that, if the king were defeated by the consul, they might have fresh troops in readiness to bring aid to their cities, but if he conquered, that they might pursue the Romans when scattered in flight. [11] Each party not only adhered to its own opinion but acted on its own decision: two thousand remained at Heraclea; two thousand, separating into three detachments, occupied Callidromum and Rhoduntia and Tichius —these are names of peaks.