The Kyffhäuser (, sometimes also referred to as Kyffhäusergebirge, is a hill range in Central Germany, shared by Thuringia and Saxony-Anhalt, southeast of the Harz mountains. It reaches its highest point at the Kulpenberg with an elevation of . The range is the site of medieval Kyffhausen Castle (Reichsburg Kyffhausen) and the 19th century Kyffhäuser Monument; it has significance in German traditional mythology as the legendary resting place of Emperor Frederick Barbarossa. Etymology The origin of the name has not been conclusively established. Kyffhäuser (formerly also Kiffhäuser) probably stems from the Low German word cuf, meaning "head" or "peak", and huse, "house". Other explanations refer to kiff, "quarrel" and the historic castles at the site. Geography The Kyffhäuser is a small Mittelgebirge located in the Kyffhäuserkreis district of Thuringia and the Mansfeld-Südharz district of Saxony-Anhalt, not far from the larger Harz range to the northwest. The range has a length of , from west to east, and a width of . The highest point at the Kulpenberg, with the Kulpenburg TV tower, is located near the village of Steinthaleben in Thuringia. The range borders on the Hainleite hill chain and the fertile Goldene Aue basin in the south. Large portions are protected as a nature park. Some parts of the range on the western and southern slopes are karstified and bare of trees, covered by calcareous grassland. The area shaped by numerous sandstone quarries today is the site of a geopark, comprising the Kyffhäuser Monument, the Barbarossa Cave near Rottleben, the Kaiserpfalz at Tilleda, and the Bilzingsleben Paleolithic site. The Schlachtberg hill on the southeastern rim near Bad Frankenhausen was the site of the decisive Battle of Frankenhausen during the German Peasants' War in 1525, commemorated in the monumental Early Bourgeois Revolution in Germany by Werner Tübke. History The settlement of Tilleda, located below the northern rim of the range, was already mentioned as Dullide in the early 9th century in the Breviarium Sancti Lulli register of Hersfeld Abbey. A Kaiserpfalz at the site is attested by the 972 Marriage Charter of Empress Theophanu. Numerous stays of her husband Otto II, as well as by his successors Otto III, Conrad II, and Henry III are documented by deeds they issued here. During the 11th century, Tilleda was superseded by a castle on the hill above the settlement that may have been erected by Emperor Henry IV during the Saxon Rebellion.