The Kyffhäuser Monument (German: Kyffhäuserdenkmal), also known as the Barbarossa Monument (Barbarossadenkmal) or the Kaiser Wilhelm Monument (Kaiser-Wilhelm-Denkmal), is a monument on the summit of the Kyffhäuser Mountain (highest elevation: 1,574 feet) near Bad Frankenhausen in the state of Thuringia in central Germany.

The monument, which totals 81 metres (267 feet) tall, was built in 1890-96 to plans drawn by the German architect Bruno Schmitz (1858-1916) atop the ruins of the medieval Fortress of Kyffhausen. The monument was initially proposed by the 19th Century German War Veterans Federation, which under the name Kyffhäuser Federation took over its maintenance after 1900.

Stylistically, the Kyffhäuser Monument recalls the castles and fortresses of the Hohenstaufen period in Germany in the 12th and 13th centuries. It was intended to suggest that the Prussia-dominated German Empire founded in 1871 was the legitimate successor to the Holy Roman Empire of the German Nation, which existed from the 10th century until 1806. It also signifies the national theme of decline and rebirth.

The monument features a 6.5 metre- (22 foot) tall sandstone figure of the medieval Holy Roman Emperor Frederick I von Hohenstaufen, better known as Barbarossa (meaning "The Red-Bearded"), who appears to just have awakened from sleep. Above him stands an 11-metre (36-foot-) tall bronze equestrian statue of Kaiser William I (Wilhelm I.), the first emperor of the Second Reich, designed by Sculptor Emil Hundrieser (1846-1911) in the neo-baroque style. This composition expresses the monument's theme: That William I brought to fruition the unification of the German nation that had been so long desired since Barbarossa's time.

Towering over the monument is a 57 metre (188 feet) tower topped by a huge imperial crown. By climbing a 247-step stairway, one can reach the top of the tower and obtain an excellent panoramic view.

An adjacent building features exhibits depicting the medieval Kyffhausen Fortress and the Legend of Barbarossa, which held that Frederick Barbarossa, who died during the Third Crusade, was sleeping under the Kyffhäuser Mountain and someday would awaken again to life when Germany needed his leadership.

The Kyffhäuser Monument is the third-largest monument in Germany, after the Völkerschlachtdenkmal (Battle of Nations monument) in Leipzig, commemorating a pivotal 1813 victory in the war against Napoleon, and the Kaiser Wilhelm Monument at Porta Westfalica, both of which also were designed by Bruno Schmitz.