Photo: Front view of the Imperial Crown: cross is an addition from the early 11th century; the arch dates from the reign of Emperor Conrad II (ruled 1024-1039); the red velvet cap is from the 18th century. It is made of gold, cloisonné enamel, precious stones, and pearls.
The crown is of the King of the Romans, the rulers of the German Kingdom, since the High Middle Ages, from when most of the kings were crowned with it. Probably, it was made somewhere in western Germany (10th century). The Imperial Regalia of the Holy Roman Empire, especially the Imperial Crown, were all kept 1424-1796 in Nuremberg, Franconia, and could only leave the city for the coronation. Now the crown and the rest of the Imperial Regalia are exhibited at the Hofburg in Vienna, officially ‘until there is again a Holy Roman Emperor of the German Nation’.