Lucius Coelius, a commander in Illyria, remained inactive while Perseus was there. After Perseus returned to Macedon, Coelius tried to recover Uscana, but was repulsed and went back to Lychnidus. He sent a detachment to the area to receive the hostages from the cities which had remained loyal (they were sent to Apollonia) and from the Parthini (a tribe of southern Illyria), who were sent to Dyrrhachium (modern Durrës, Albania). Perseus was invited by the Epirots to attack Aetolia and marched on Stratus, the strongest Aetolian city, with 10,000 infantry and 300 cavalry. He could not pitch camp on the snow-covered Mount Citium and had to encamp elsewhere. He then was held up at the River Aracthus because of its deep water. He built a bridge, crossed, and then met Archidamus, a distinguished Aetolian, who had persuaded the nobles to betray Stratus. However, while he was away, the pro-Roman faction called in a Roman garrison. Dinarchus, the commander of the Aetolian cavalry, also arrived with 600 infantry and 100 cavalry to support Perseus, but when he saw the changed situation he switched allegiance to Rome. Due to the winter weather, Perseus abandoned Stratus, and went to Aperantia, which, through the influence of Archidamus, willingly surrendered. Archidamus was made its governor, while Perseus returned to Macedon. L