Aachen has been around for millennia. The Romans nursed their war wounds and stiff joints in the steaming waters of its mineral springs, but it was Charlemagne who put the city firmly on the European map. The emperor, too, enjoyed a dip now and then, but it was more for strategic reasons that he made Aachen the geographical and political capital of his vast Frankish Empire in 974 – arguably the first empire with European dimensions.