As armies strengthened their siege engines and developed artillery capable of pummelling settlement walls, defenders were forced to adapt their tactics and equipment to counter the threat. A gateway flanked by towers was no longer enough to repel a determined foe. Defensive towers and platforms grew to accommodate not only archers and slingers, but also artillery engines as well. During the siege of Lilybaeum in 274BC, the Carthaginians placed catapults along the length of their walls to fend off the armies of Pyrrhus; his men were forced to abandon the attack by the weight of the defensive artillery bombardment.
