greater visibility from which the garrison could employ their guns, and the complex set of courtyards and baileys provided additional opportunities for defenders to retake portions of the castle that had fallen. Cannon were rare in Japan due to the expense of obtaining them from foreigners, and the difficulty in casting such weapons themselves as the foundries used to make bronze temple bells were simply unsuited to the production of iron or steel cannon. The few cannon that were used were smaller and weaker than those used in European sieges, and many of them were in fact taken from European ships and remounted to serve on land; where the advent of cannon and other artillery brought an end to stone castles in Europe, wooden ones would remain in Japan for several centuries longer. A few castles boasted 'wall guns', but these are presumed to have been little more than large caliber arquebuses, lacking the power of a true cannon. When siege weapons were used in Japan, they were most often trebuchets or catapults in the Chinese style, and they were used as anti-personnel weapons. There is no record that the goal of destroying walls ever entered into the strategy of a Japanese siege. In fact, it was often seen to be more honorable, and more tactically advantageous on the part of the defender for him to lead his forces into battle outside the castle. When battles were not resolved in this way, out in the open, sieges were almost always undertaken purely by denying supplies to the castle, an effort that could last years, but involved little more than surrounding the castle with a force of sufficient size until a surrender could be elicited. The crucial development that spurred the emergence of a new type of defensive architecture was, thus, not cannon, but the advent of firearms. Arquebus firing squads and cavalry charges could overcome wooden stockades with relative ease, and so stone castles came into use. Azuchi Castle was destroyed in 1582, just three years after its completion, but it nevertheless ushered in a new period of castle-building. Among the many castles built in the ensuing years was Hideyoshi's castle at Osaka, completed in 1585. This incorporated all the new features and construction philosophies of Azuchi, and was larger, more prominently located, and longer-lasting. It was the last bastion of resistance against the establishment of the Tokugawa shogunate (see