Xanthippus led the army of 100 elephants, 4,000 cavalry and 12,000 infantrythe latter included the 5,000 veterans from Sicily and many citizen-militiaout of Carthage and set up camp close to the Romans in an area of open plain. The precise site is not known, but it is assumed to be close to Tunis. The Roman army of about 15,000 infantry and 500 cavalry advanced to meet them, and set up camp about away. The next morning both sides deployed for battle. Xanthippus placed the Carthaginian citizen-militia in the centre of his formation; with the Sicilian veterans and the freshly hired infantry divided on either side of them; and with the cavalry equally divided on either side of these. The elephants were deployed in a single line in front of the centre of the infantry. The Romans placed their legionary infantry in their centre, arranged in a deeper and denser formation than usual. Polybius considered this to be an effective anti-elephant formation, but points out that it shortened the frontage of the Roman infantry and made them liable to being out-flanked. Light infantry skirmishers were positioned in front of the legions, and the 500 cavalry were divided between the flanks. Regulus apparently hoped to punch through the elephants with his massed infantry, overcome the Carthaginian phalanx in their centre and so win the battle before he needed to worry about being attacked on the flanks.