Miners found a world of opportunities in Trent. Allured by prospects of mining profits, German miners who settled in the Adige Valley were unlike any other form of agrarian labor. Undeniably, all labor produced value. But several historical conditions put miners above shepherds and peasant farmers. Miners had the benefit of accumulated experience and knowledge learned in other galena basins of Europe. They exploited mines in the Harz Mountains, Freiburg, Corvey, and Mansfeld in Saxony; Alsace in the Vosges Mountains; and various locations in the Sudetes in Poland. Miners brought useful mining skills, ingenuity, and dexterity to war campaigns of the empire. Digging tunnels and trenches with the intent of besieging towers and building various rotam adapted to military scenarios were among the mining skills crucial to the success of armies. These men built ‘formidable stone fortifications and ingenuous siege techniques’ characteristics of European warfare. Crusading wars against Islamic Andalusia, Eastern Europe, and Jerusalem and Palestine increased demand for men with these skills. Relying upon men dexterous in the use of pickaxes and mills, aristocratic milites perfected the tactic of laying siege to cities.