The battle was fought in early June 339 BC. Timoleon was positioned on a hill with his army, overlooking a plain where the Carthaginian army was located. The Crimissus river separated the two armies and covered the plain in a thick fog, making it impossible to see the Carthaginian camp. However, the noise signaled to the Greeks that the Carthaginians were going to cross the river. The sun had risen higher in the sky and dissipated the fog in the plain, making the Carthaginian troops visible. The four-horse chariots were at the vanguard of the army. Behind them was infantry which the Greeks identified as Carthaginian citizens and at the rear were the foreign troops. Timoleon noticed the army was separated by the river, giving him a good opportunity to attack. He decided to send the cavalry ahead to prevent the Carthaginian citizen infantry from forming their phalanx.