Nuremberg Castle is a group of medieval fortifications on the sandstone ridge of Nuremberg's historic center. The castle, along with the city walls, is considered one of the most powerful medieval defenses in Europe. In the Middle Ages, Germany had no capital, but the king went from one castle to another. Thus, the castle of Nürnberg became an important imperial castle, and in the subsequent centuries all the German kings and emperors lived in it. The Nuremberg Castle has a history of 1,000 years.