Improved Siegecraft (Civ3)/Civilopedia

As castles grew ever more intricate, and engineering added specialized building processes and architectural improvements,
the siege engines of the Romans became inadequate, and more impressive and powerful siege engines were needed. The ultimate
siege weapon not powered by gunpowder was the trebuchet, a counterweighted cousin to the catapult able to hurl a 30-pound
stone nearly 200 yards. Some were built so massively that they could hurl missiles weighing up to 660 pounds. Beyond the
development of trebuchets, new siegecraft methods also included specialized tools such as giant drills and screws to bore
through walls and levers to chip out mortar and pry stones apart. The final, and most dramatic method of breaching walls was
mining. This involved digging shafts under walls and towers, then burning the timbers supporting the shafts so that the walls
would collapse into the hole. The only method to counter this attack was a counter-mine, and when the two shafts met, opposing
troops would sometimes fight in cramped, nearly lightless tunnels.