Aachen, also known as Bad Aachen, and in French and traditional English as Aix-la-Chapelle, is a spa and border city in North Rhine-Westphalia, Germany. Aachen developed from a Roman settlement and spa, subsequently becoming the preferred medieval Imperial residence of Charlemagne, and, from 936 to 1531, the place where 31 Holy Roman Emperors were crowned Kings of the Germans.