Shortly before the start of the siege, the Achaean council members decided to accept Macedon's war conditions after all. Aratus sent his son to Macedon as a hostage. Antigonus was ready with an army of 20,000 infantry and 3,000 cavalry. When Cleomenes heard of the Macedonian intervention, he abandoned the siege of Sicyon as fast as possible, moving to the Isthmus of Corinth, a better position from which to meet the northern threat. Aratus went to meet the Macedonian king near Pagae: