From DT Online
The Siege Towers were used by Greeks, Romans and into the Middle Ages to protect attacking troops as they attempted to overcome the defensive walls of fortifications (e.g. city walls or castles).
The Romans referred to them as Turris (Latin for Tower) and Ancient Greeks knew them as Helepolis (meaning The Taker of Cities). Essentially, they were large square towers, perhaps as much as 40 metres high or more, and divided into several storeys (e.g. the one used by Demetrius at the siege of Rhodes, B. C. 306, was some 40m high, 20m wide and divided into 9 storeys). Such large machines would be built on site but smaller versions may be brought forward in pre-fabricated ‘kit’ form.
They were covered on 3 sides (e.g. with animal skins or even iron cladding) for protection from defending archers and mounted on wheels or castors so they can be moved up close to the fortification. The various storeys were filled with troops (e.g. archers and pikemen) and the bottom storey could house a Battering Ram and/or provide cover for troops who were digging under the fortification walls to undermine them so that they may collapse. The top storey was high enough to allow attacking archers to aim down on to defenders behind the fortification walls. Siege Weapons such as Onagers or Ballistas could also be housed on top. A Drawbridge type device (i.e. Corvus) could be lowered on to the top of the fortification to enable attacking swordsmen to go over and engage with defenders directly. A Roman Turris would protect troops on the top with a Testudo type roof.
Siege Towers were formidable machines and usually succeeded in overcoming fortifications. They were made largely of wood so the most effective way of resisting them was to try and set fire to them but the animal skins they were covered with were usually wetted to minimise this risk. Alternatively, defenders would flood the area in front of them and create a moat so they became bogged down. They could also use long poles or grappling irons to try and take hold of them and pull them over. Fortifications would house their own Catapult type Siege Weapons and any approaching Turris would be their first target, but the Turris would often also have a Catapult with which to retaliate. Additionally, defenders could build towers on top of their walls to regain a height advantage.
Activity: Find out about Roman Siege Equipment (e.g. Vinea, Pluteus, Mantelet, Testudo, Musculus, Helepolis, Turris, Corvus, Ballista, Onager, Mangonel, Trebuchet, Aries (Battering Ram) and construct a working model or models using Stripwood Technology.